Bunch of different options. I actually couldn't tell the difference in latency from through a monitor when I just used steam in home streaming / remote play as steam in box streaming / not really remote play.

I'd say in order of seamlessness: KVM switch or monitor input switch Looking-glass parsec, steam in home streaming

I have a KVM switch as well but I kind of prefer to run things in a window.

There's a couple quality of life things about running windows in a VM as well. When it goes on it's update parade I can just close the window and ignore it. And with snapshotting a bad update can just be rolled back.