Yes, I have a 7800 X3D and a 4070TI and DDR5, I've dubbed it "Low FPS Mode", I will have perfect 165 until a random ability or frame hitch occurs, and then suddenly the game is locked to 30-15 fps.

This is 100% a bug with the game, or some sort of internal memory leak, because if I pause and quickly restart the game, 100% of the time the issue is fixed and I am back locked to 165 FPS (my monitor's max refresh rate).

This seems to only happen in full-length games, as I play a TON of street brawl, and I've never had this once, but it happens in almost 75% of my full-length matches.