Scenario 1 - Next gen consoles should be coming in 2022 - 2024 on 3nm APU, with 128GB of RAM, and 2TB NVMe.

If people want discs next gen, then I think they should have to buy the add on, but I could also see support dropped all together. At any rate, discs will never be anything other than a means to get data a mass storage device, where the games will actually be played from, just as they are now.

I expect all three manufacturers to support their games over multiple form factors in the coming years, from phones, to tablets/handhelds, to the consoles. They will try to get rid of discs as soon as possible, by driving the value of digital up so high, that you would have to be insane not to buy digital.

Basically, I expect that if you buy a disc next gen, you will be locked to your console. If you buy digital, you will be able to play on your console, your phone, your tablet, your laptop, or your PC.

Example PS5/XB4 2022 - 2024
-3nm APU
-8 Core/ 16Thread CPU
-~25TFLOP GPU
-128GB HBM3
-2TB NVMe User Expandable
-6x USB 4.0

Optional Disc Drive
-Any USB 4.0 USB UHD Drive

Cartidges.

Technically, that plug and play memory card is an internal drive. Funny interesting fact, a 2280 NVMe SSD is  probably 10 times smaller than the carts of old. 

The only real issue with a driverless console, is that it will be abused by publishers. If publishers know that buying a drive for your console is now an add on, they would just take advantage of that to not release their games on disc. rather, a "disc version" of the game will become something you only see from publishers only afer they have sold like 3-5M copies of their game digitally. So you may not see the disc version for at least 6-9 months after the game was released digitally.

For them, there are lots of benefits to doing that;  1) not having to worry about piracy 2) not having to worry about the used game market 3) lower cost to publish a game....etc.

There should ALWAYS be a physical media reader of some sort, and not throw in as an external one.If reading speeds are an issue, everyone should then take Nintendo idea, and go back to cartriges.But never digital only, or without a built in blu-ray or card or whatever reader.

Cartridges are slower and more expensive to manufacture. Cartridges have a natural place due to their small size in portables, but I don't think will ever be the norm for consoles as size is not important to home consoles. I think digital + install from disc will remain the norm for at least another generation.

Always good to have options and people still rely on physical format for the most part. I hope it stays thst way, even though I myself have been buying like 3 for ten with digital in the lead.

It's more likely they will do 2 versions of consoles, one with a drive, the other without. Up to you which you get, one without being cheaper obviously. I just don't think we are there yet with digital only (no resell), and certainly not with cartridges (still too expensive).

With sd cards and flash memory getting larger and more affordable there is no need for anything else. It is also one of the fastest possible types of memory if implemented in the right way. Why waste space for a HDD or drive if the same amout of memory fits into a SD or micro SD card, in the future even for a lower price.

Cardridges are the fastest possible storage, faster than any HDD or optical media could ever be. And production costs will soon be lower too.

Cartridges are slower than spinny disks?

No, that sentence means "Cartridges are slower to manufacture, and more expensive to manufacture".