On what do you base that claim though? If it's because the frame rate still scales, that's not it - it does for me too.
Looks like everyone who has anything less than the very latest generation super high end CPUs are getting terrible (sub-60) framerates even though the general consensus is that frame times are stable for mostly everyone. All accounts is that X3D doesn't help, if anything the result is actually worse due to the relative clock speed hit, it can't help due to the way the functions are implemented.
I was told that due to the force inline on large functions issue, the game is written in such a way that leads to the cache miss rate being extremely high, in such a scenario, there's no replacement for brute IPC - and with the king of high IPC CPUs in my PC, I can tell you that the game still suffers plenty. It is playable, of course, it couldn't not be with such insane specs, but this game will need some pretty serious patching to address performance on average to good gaming PCs. Anything socket AM4 for example, even the likes of 5800X3D and 5950X will have a rather vexing degree of trouble with a solid 60fps experience. They are not slow CPUs.
That's probably because it's a bogus reading. It's happened with a few games in the past. Using Special K for a global 72 fps (half refresh rate) synchronized experience, my RTX 4080's fans don't even turn on. Have heard a similar report from a friend that owns a 3090 on a Zen 2 platform (I believe he runs a 3900X), the frame rates hover between 30 and 40 for the average lows. The thing we have in common is that our GPUs are bored asleep.