While a move to Arm promises users with lighter and more efficient PC hardware, the state of PC gaming on Arm has a lot of catching up to do as the developer ecosystem remains in infancy.
I'm not sure what games do work, but I'm surprised over half of what they've tested are in a good state considering it's running on an emulation layer with immature drivers. Additionally, anti-cheat can't really be helped, that's an issue we've been dealing with on Linux for ages as well. I don't think anyone was really expecting it arm on windows to overtake x86 instantaneously, but from a technical standpoint it's not a bad start. Of course, things could be better, but they could be much worse.
Microsoft convinced hardware manufacturers to support UEFI and TPM overnight. If they just said next Windows is going to be ARM only, software manufacturers would have to follow.