I’m pretty sure an inexpensive laptop + Steam Deck would be about the same price (or less!) as a gaming laptop.
I got my E-series ThinkPad a few years ago for $400-500 (E495, first AMD ThinkPad E series), and my Steam Deck for $530. So I paid about $1k for the pair. Gaming laptops start around $1k and go up from there.
It works well for me, but then I don’t need a GPU for my non-gaming laptop use, so I can get away with it. YMMV depending on what you need the laptop to do.