Plenty of things, but the first that came to mind was the same as OP. The Steam Frame looks really cool, but at the price it's a whole thing.

Same for other electronics - a Framework laptop, building a new desktop (good luck to me there), a Steam Deck.

Lots of newer video games. It's easy to turn down some of them, because I know I haven't made time to play a lot of what I already have. Likewise for books in general, where money isn't a bottleneck but time and space are.

Pokemon cards - just recently had a mini-convention day here in town with a bunch of collectors/vendors selling. Made me really want to go back and fill out my weak collection of WotC classics, but the price (vs how much I care) is a bit prohibitive.