Microsoft has long wanted to get vendors out of the kernel. It’s a huge privacy/security/stability risk, and causes major issues like the Crowdstrike outage.
Most of those issues also apply to kernel anti-cheat as well, and it’s likely that Microsoft will also attempt to move anti-cheat vendors out of kernel space. The biggest gaming issues with steamOS/Linux are kernel anti-cheat not working, so this could be huge for having full compatibility of multiplayer games on Linux.
I don’t think chain of trust and security through kernel-level access are fighting the same problem.
Usually chain of trust is to prevent app tampering, and kernel-level access is to prevent memory tampering.
I assume Windows is creating a new API for applications to monitor certain regions of memory for tampering without needing kernel access.
There already is a API for this with ebpf for Windows and it is the same API that can be used on Linux (because it originates from Linux).
https://microsoft.github.io/ebpf-for-windows/
EBPF still runs in Kernel space but in a much more limited and confined way.