It is the same code whether used in Monterey or Big Sur (Safari 15 uses webkit 17612.2.4.1.2 while Safari Technology Preview uses webkit 17613.1.1.5). Although I mostly use Monterey, we also have two macs running Big Sur and the experience is identical on both OS versions.

If we knew what it was we were doing, it wouldn't be called research, would it?

— Albert Einstein