Do you seriously think developers would drop support for two-year-old machines with 30m install bases? Or that they wouldn't explicitly highlight which models a piece of software is compatible with?
I know hardware cost is looking like the last advantage consoles have, but it's still there.
It isn't about dropping support, but that in terms of investment part of the appeal was what you bought was the best for a set time. The manufacturers could combat this by opting not to call their hardware refreshes mid-cycle names like the PS4.5 but instead just the PS5 and that may alleviate some of the mindset, but the shorter 3-4 year cycles will have people making comparisons to an investment in PC gaming if they feel their money isn't worth spending towards a short-cycle console before the next refresh. In short, many people just aren't interested in an iterative model of business, supported or not, when it comes to a specialized-use device such as a games console. Marketing them as entertainment centers didn't work, and people responded to the console that claimed itself as games first. Switching it upon them will just drive them to PC. Not everyone of course, but a substantial number (IMO).
As far as PC gaming goes, the costs are much lower today than they used to be, and it's extremely easy to get into. You just buy the game, download it, install it, and it will automatically patch itself and be ready to play, the same as consoles. Especially so with Steam. Graphics settings are very easy to get used to, they're just sliders that you play around with for five minutes until you understand which does what. On hardware complexity, many pre-built gaming PC options exist, ranging from low to high tier, that would have you set for at minimum the rest of the console generation and in many cases beyond. The hardware entry cost is still in consoles' favor, and I hope it stays that way, but iterative consoles will nullify this to an extent given the low cost of PC games that quickly make up for the initial entry price.
That all being said, ease of use is still on consoles' side at the moment, the margin is just lower than it used to be. For them to still be viable longterm they need to establish or maintain the identity they've forged. What that entails, I don't know. I just don't believe going iterative helps it.