Playable, yes. Easy, depends on your ability to work with software. I found it decently easy but not easy enough for me to continue using. Turns out my steam library has plenty for me to play

Depends on the game. Some run extremely well to the point where it’s identical to the Switch performance but some of the more demanding games like Tears of the Kingdom are going to be a subpar experience. Tinkering is expected if the game doesn’t run at the 30fps/60fps that you want it to run at.

I’m literally playing Mario 3D World for Switch right now on my Deck, runs beautifully!