IMO, Nintendo has always been a bit behind on hardware, and most of their draw is the exclusive titles.

I have both a switch and a steamdeck, and if a game is offered on both, I'll buy the PC/Steam version.

The deck is larger, but actually fits quite well in my large hands, and I'm quite impressed of the amount of games that run well on it. It's not a replacement for a true gaming PC, but it's access to the existing steam library (and other PC games if you are clever) makes it quite an offering.

The devices have majorly different target markets, which makes it hard to compare them.