For what it's worth, I just re-tried switching the display mode from borderless window to fullscreen, and lo and behold, it works! The framerate is back to pre-HF21 levels, and the game is eminently playable again.
I tried the same trick when the frame rate problem first arose, but to no avail. I don't know if it's the subsequent hotfixes or the fact that this time I made the switch in the starting menu, before I'd loaded the save file, but anyway I'm back to the races!
2020 M1 MBP, 16GB RAM, mostly maxxed settings, using a Dell U2421HE monitor
Nope, Just tried. In any window setting (borderless, regular or full screen) I get the same behavior.
Fly through House of Hope Raphael's Boudoir from the spa to the door with steps afterwards leading to the inner corridor.
Comes to a screeching halt < 1fps.
Not sure which shaders or effects are getting hit here, but something is clearly wrong.
M2 Max 64gr 12cores 38gpu.
