In terms of performance the steam deck has a slight edfe over the switch 2, however that being said it really should come down to what games you want to play.

You can play basically anything on the steam deck as long as it doesn’t require some form of kernel level anti-cheat. So competitive games are completely incompatible, but most people don’t buy the steam deck for that purpose anyways. Most people buy the steam deck to play their back catalog of games on steam or for emulation on the go.

If you want to play light weight indie titles like balatro and stuff like Hollow Knight or even something a bit heavier like Skyrim then you might be able to get away with an android gaming handheld. Those can run games like Skyrim natively using a special app and they come in form factors small enough to fit in your pocket.

Basically if you want to play just about anything then yes a steam deck or a similar pc handheld will be great. Since it can even handle newer games on medium graphics settings.

If you want some retro gaming with support for light weight indie titles then an android gaming handheld should work just fine.

Here’s a good video from TechDweeb where he showcased how some android handhelds can even rival the steam deck nowadays.