Kid, as I said before. You don't know anything about economy and technology.

Consoles are not a PC. PS4 doesn't have 8GB GDRR5, it's actually has 16x0,5GB of unified memory. That's why the bandwidth is so high (176GB/s). 16GB of GDDR5 will be enough to run all games in 4K/60 if needed.

You are also completely ignoring the fact how difficult and costly it is to implement HBM. GDDR is just slapping modules on a PCB. HBM is using complicated interconnects and thru-silicon via's to connect delicate parts together. The kicker is that the company that can handle that isn't the same as the one that makes the HBM itself. So a high-end GPU has to go through 2-3 different companies possession which is a lot of incurred cost.

The stuff you write is ridiculous. It doesn't meter if you are using GGDR5 or GDDR6/HMB2 for the 4K resolution! It's not like that you need more ram if you are using GDDR5 instead of GDDR6.

Consoles are not a PC. PS4 doesn't have 8GB GDRR5, it's actually has 16x0,5GB of unified memory. That's why the bandwidth is so high (176GB/s). 16GB of GDDR5 will be enough to run all games in 4K/60 if needed.

It does matter.
That's not to say GDDR5 cannot get the job done though if you go wide enough. - But that costs.
To drive GDDR5 higher in clockrates and/or have more chips to take it wider to match GDDR6/HBM2... You need a more complex memory controller/crossbar. - Guess what? That costs transistors on the SoC, that costs TDP that could be used for GPU clock rates.
And that is ultimately the crux of the issue.

GDDR6/HBM2 in general provides not only larger capacities, but loads more bandwidth economically.

There is a reason why Microsoft opted for faster and more (12GB rather than 8GB) GDDR5X Ram on a 384-bit bus than GDDR5 on a 256-bit bus to drive 4k. (And even then still doesn't guarantee it.)

That is generally how all ram works, Lots of small capacity chips parallelize the load.
Consoles use PC technology remember.

For example... The Playstation 4 has 16x memory chips each with a 512MB capacity.
Each chip has a 16-bit data path to the memory controller. Combined, that gives it a 256-bit total memory bus.
Each chip also operates at 2.75Ghz. (Quad data rate remember.)

Which provides it with 176GB/s of bandwidth.

There are Playstation 4 revisions which have dropped the 16x memory chips in favor of higher density 8x 1GB chips at the same clock rate, each with a 32-bit path to provide the same overall bandwidth.

But guess what? The Playstation 4 struggles to obtain 1080P reliably, it has no chance of 4k with any degree of image quality... Which completely undermines your statement, unless of course I have misconstrued it?

I can't be the only one here that doesn't give a crap about 4K. Right?

time to start saving up for that PS5 tho