I can't imagine the PC gaming market surviving the extinction of sub-$300 GPUs unless we get affordable yet sufficiently powerful IGPs with on-package memory to take over the market segment.
We will get 4030 for $300 so PC gaming will be just fine!
In reality what happens is the same as with cell phones.
New gen 4050 are gonna be $500 and that is the weakest we are gonna get (maybe)
The price of 3050 will drop to $350, the price of 2050 will drop to $300 or even $250 and vola Nvidia has cheap gpu for low end… Aka last generation GPUs are sold at good profit as an low end options so that manyfacturers don´t have to sell anything at real discount = profit to the company and stock holders.
So PC gaming will not die, people just are gonna use two or tree generation old hardware, when they build new gaming computer, unless they have more money than brain cells and they buy the newest generation. And there are enough customers to buy these next gen products at incredibly high prices! 4090 at 2500€ are sold out! 4080 at 1800€ are not sold out, but still selling, while normal people buy 3000 series that is still above MSRP! Nvidia can only say that they have done good job!
I personally have so big steam game library that I will newer go to consoles. I may be forced among the people who buy two or tree generation old GPU hardware, but that is that. AMD and Nvidia still get my money and at the same time get even more money from people who buy the next gen tech. They only win in all situations and now they win even more than before.