A:Answer Yes, I'm using a Dell G2724D that's 1440p and 165hz when using DisplayPort, 144hz with HDMI. It works beautifully.
Now, will you actually get 100+ FPS in whichever game you're playing? Depends. I can in older stuff like CS:GO and BF3/BF4, but stuff like BF 2042 is hovering around 80 FPS @ 1440p with low settings and DLSS on. This 3050 6GB isn't bad, but don't expect to max out newer games and keep your framerate high.
This screen is so beautiful that I think it's actually fine for 1080p/60, so that'll come in handy for games that it chokes on in 1440p.
Not sure about the KVM switch, but my USB-C hub works fine aside from not being able to do high refresh rate. This laptop has the ethernet port anyway, so it's null for me.