I have a ~10tf 5700xt that boosts and holds 2.1ghz right now. It isn't a 4k card for current titles. I guess maybe a 4k30 card, but that's right now. In a couple years it won't be because it's literally outclassed by an XSX and is about to be massively outclassed by new cards. It is also already CPU limited with a 5.0ghz 8700k at 1440p.
I'm not actually concerned about PS5 performance in general because it really is sort of apples and oranges. The settings/eye candy aren't the same, more optimization in the console space, etc.
But if devs are already saying they are throttling the CPU to lock the GPU clocks, well yes I don't think it's crazy to think that will change overtime and we can expect to see more checkerboarding and a fair amount of 30fps titles, unless they adjust their objectives for 60fps which means higher CPU clocks and lower GPU clocks/eye candy. And yeah if anything people saying this had been "debunked" 5000x, no, it really hasn't. Dropping CPU clocks to hold GPU boosts literally tells you the psu isn't cut out for the maximum performance of the console. Like it's right there, an admitted, open perf compromise in order to hold GPU clocks.
I don't think any of this goes against this rumor. And in the console space I fully expect XSX to also be largely 30fps within a few years.
I'm not sure exactly what's controversial about 30fps console gaming. It's literally always how it goes for the most part especially later into the gen unless we see another big hardware refresh, which of course, requires buying new hardware because the launch specs are starting to lag.