I don't think the slightly thicker HDDs would be an issue for a home console.

On a side note, maybe MS and Sony will use stats to determine if HDD or SSD is the best route. For example, if MS really wants people using the subscriptions like Xbox Live ("free games"), EA Access or Game Pass then a massive storage HDD is crucial. But if the average user is just playing a few titles that fits in a 1TB SSD, well moving to SSD makes sense.

It's interesting you mention 2020 and prices continuing to drop... The same will hold true for mechanical drives as well you know.
2tb drives are getting cheaper and cheaper.

It's interesting you mention 2020 and prices continuing to drop... The same will hold true for mechanical drives as well you know.
2tb drives are getting cheaper and cheaper.

If the drives are only a terabyte or two... External storage will still be a must.

They aren't. It's just a common design choice that Microsoft and Sony take for whatever reason.
Notebook drives tend to have the advantage of lower heat and noise as well.

And its not just about loading times, its also about streaming in assets to avoid pop in or sectional loading. As these assets become bigger so will the bandwidth required to stream them in.

And dare I say.... it may even end up being cheaper for them to use nand flash storage than using a HDD. Lets take that 1TB size as an example. I have no doubt that by 2020 it shouldn't cost them as OEMs more than $40 for an M.2 sata QLC nand flash SSD. But then these are consoles we are talking about. What stops them from just all out skipping the M.2 drive and solder the storage modules directly onto the board instead. How much would that cost them then? Definately less than $40.

 And while I get that consoles pretty much always go the cheapest route thats not always the case. Some times the value of a component with regards to the genera architecture of the system design will take precedence. Like using GDDR5 even though there were cheaper options. Or like using a vacum chamber even though they could have used a cheaper cooling solution ad just made it bigger.

I believe that if there is a single benefit to be gained from using nand flash storage then they would go with that instead. Especially when considerring future proofing the platform.

At the start of next gen External drives will be necessary as internal M.2 Storage would be limited to 1- 2TB due to cost. As we move into the generation, SSD Capacity is expected to make exponential leaps, while HDD has little out look for capacity gains.

By 2024 or the mid way point for next gen, we will very likely be looking at 8 - 16TB SSD's in the price range of 1 & 2TB HDD's today. People willing to pay $500, $1,000, $1,500 or more will have 32, 64, & 128TB options.

If Sony sticks with HDD, they will be limited to slow read speeds all gen, and eventuallly they will hit a wall in capacity. HDD is short term gain, mid term loss, and early obsolescence. SSD is a short term loss, with midterm gain, and late life prosperity.

I strongly doubt they will. And for a number of reasons.

If consoles opt to go with HDDs again, then in about 3 years time they could find themselves as the only ones still using that antiquated technology. I mean right now even $300 laptops come with 128GB m.2 SSDs. And then there is performance. HDDs are slow. But lets put this into context; Right now we have ~5GB of RAM available for games in the current consoles. I think its safe to say that next gen that allotment will at the very least double. Using a HDD we already have games that take around 30 - 70 secs to load in a level or stage. If the RAM size doubles and game asset sizes double too then it will literally take twice as long to load up that level. We are going into a gen of higher rez textures on everything including shadows and the usual bump in general assets and code. Thats not going to be very pleasant at all.

I really don't think they will have any problem at all launching these consoles with 500GB on an M.2 drive. Those things cost around $70 right now on amazon which means that in about 18 months they could be down to as little as $50. That means it will cost Sony and MS (OEM pricing) as little as $30 for a 500GB M.2 SSD. They just launch with that and allow ext HDD support from day one so gamers can backup games they aren't actively playing. And even allow gamers upgrade their internal SSD if they want to.

Its simply the best way to go forward. They could even get 1TB drives for as little as $50 at the time. 

Thing is, the only real cost of going with an SSD is capacity. But it comes with a lot of benefits and ensures future proofing. But the second they put a HDD in there, they build in limitations that they will never be able to overcome for the rest of that generation. Because games are always built to the lowest spec....

While having 2TB in the box would be great.... that really means nothing to an end user. If asked to be able to store 32 games as opposed to 8 games in their consoles but then choose between an all round snappier UI and loading games in 15 seconds as opposed to 50 seconds..... its my guess that speed will win everytime. 

There are other ways to get around that issue, namely compression, which tends to be CPU heavy... A few games of the 7th gen took that route for instance to get around the low bandwidth of the DVD/BD-Rom drive.

Absolutely nothing stops them from soldering it directly to the motherboard.

Well. The Xbox One did go with DDR3... And the Playstation 4 wasn't using the fastest GDDR5 anyway... And the Switch is using LPDDR4.
Not to mention the consoles only had 8GB of the stuff.

Price is the most important factor to building a console, they are cost sensitive devices that cannot have high-end components.

Microsoft used NAND with the Xbox 360, granted it was only 4GB, but the precedent is there.

How sure are you about that?
Heat-Assisted Magnetic Recording and Microwave-assisted recording are all next-gen mechanical HDD technologies that should push HDD capacities up towards 20 Terabytes per drive in a 3.5" form factor before 2020.

Mechanical Disks have stagnated for the last few years, just like CPU's and GPU's, but that won't last forever.

People have been claiming SSD's will have exponential increases in capacities for years... And we are still at only 500GB in the Mid-Range, 120GB in the low-end.

High-end mechanical disks should give a DRAM-less QLC nand SSD a run for it's money, especially in sequential reads.
Especially hybrid drives.

I mean shit... EMMC Nand drives make me want to take up smoking meth, I would prefer a semi-decent 5400rpm mechanical disk over those, especially if it's a hybrid drive.

There are other ways to get around that issue, namely compression, which tends to be CPU heavy... A few games of the 7th gen took that route for instance to get around the low bandwidth of the DVD/BD-Rom drive.

Absolutely nothing stops them from soldering it directly to the motherboard.

Well. The Xbox One did go with DDR3... And the Playstation 4 wasn't using the fastest GDDR5 anyway... And the Switch is using LPDDR4.
Not to mention the consoles only had 8GB of the stuff.

Price is the most important factor to building a console, they are cost sensitive devices that cannot have high-end components.

I would be fine with a 128Mb (or 256Mb) SSD that you keep the game you are currently playing with a 2TB HDD to store other digital games and an easy way to transfer from one to the other when you want to change the main game that you wish faster time.

7th gen.... which when looking at the tasks they had to do had CPUs that were in comparison better than what we got in the 8th gen. Compression is a thing though, but as you said its a work around.

And thats what I believe could happen. Its not something they could have done this gen but as long as they can put 500GB-1TB of internal storage in the consoles at around $40 or under I think its what they would do. It also has the added benefit of simplifying the entire build process. And it would be cheaper too. 

I dont thing using about a quarter of the entire consoles budget for RAM is what I would call cheap. And while it may not have been the fastest GDDR5 ram out there, it was cutting edge for a console in 2013. It was also not even "cheap" back then. Its easy to look at GPUs now pushing an average of 8GB and up and forget that when the PS4 launched there hardly was a GPU on the market that had more than 4GB of GDDR5. 

Yes it is. But not always as how you look at it. 

You are quick to point out the limitations of consoles but refuse to recognize their advantages. If sony is making a console today they are not just looking at its price right now but looking at its price over the next 6-10 years. Their are alot of options open to them too being that they are making a proprietary box. 

They used Around $30 to put in a 500GB HDD in 2013. Today what is probably about the same amount of money is getting them 1TB. So the real question here is how much SSD storage are we going to get with $30-$40 dollars in 2020. Its even possible they make a 500GB model for $399 and a 1TB model for $499 or less.

But going with a HDD is just wrong to me. Its Literally building in obsolescence from day one.  

Too complicated. They would sooner put in only 500GB of storage in there than do any hybrid stuff.

As long as they allow external HDD then they are kinda accepting hybrid, be it either as having 2 internal memories or allowing external where you would transfer saved game to SSD before starting, which is different from regular hybrid and doing cache as far as I know.