Windows on Arm is not ready for the complexities of the PC gaming landscape

Yet. But as all technology is continually developed, it will get there. I also have to wonder if the incompatibility is on Microsofts side or on the game developers side. Some games have incompatibility due to anticheat, is that because Windows on ARM doesn't support it or because the anticheat doesn't support ARM architecture?

It's in a state similar to Linux gaming, it depends on the game. It's potential is making Intel and AMD sweat, though. AMD is already designing ARM CPUs, but so is NVIDIA. It could be very good ... or very bad if they attempt to embrace, extend, and exploit with their own chips.