Friend of mine was suffering thermal throttling due to factory overclock of (+50mv) followed by BIOS update 1.07 on Predator PH315-53 (2020) and decided to risk backward BIOS compatibility by flash previous BIOS 1.06 and good thing is it's backward compatible. For those who are having locked out ThrottleStop and Intel XTU, can flash older BIOS to restore and fix thermal issues as well.
For the proof, posting photographs below and if you still don't want to risk, it's all up to you after all that is your laptop and money.
As you can see now the clock speed are unlocked.
Hope it helped, sorry for the image quality and if you are still skeptical about it then don't flash.