I didn't try the betas so not sure what they were like, but this release is solid. I'm running the KDE version, the animations are smooth af, and everything's fast (M1 MBA). Haven't had any crashes or major issues yet. Only issue for me is that the built-in mic doesn't work yet (but the speakers and webcam do), so hopefully that's sorted out in the near future.
My previous experiments with Linux on Macs were all Intel-based ones and they always felt a bit clunky and buggy, but Asahi doesn't feel that way at all.
Haven't tested out any of the Box64 emulation/gaming stuff so might give that a try this weekend and see what's that like (I believe they've only got basic OpenGL support right now, no Vulkan yet but that should be coming soon). But there's a lot of development going on in this space in general (x86 emulation + gaming on ARM), so it's pretty exciting to be in the midst of it and watching it evolve!
Unlikely. Best option would be to it in a VM, or install a second distro to your drive and upgrade it to Plasma 6.