1. It’s comfortable.
2. No, it’s not as comfortable as a PS5 controller.
3. I don’t play souls games.
4. Most first player type games play pretty well if they play at all.
5. It’s not like PC gaming in 2023 (or ever) could be considered to be trouble-free in general, so if I’m being honest, I think Steam Deck is actually a great experience when things work. If you think of games you’d want to play on it, most of them play pretty well.

Write them. They often have good customer service.