Certainly up for their handheld..most probably.
The only thing that stops me exclusively only having a Steam Deck is the collection of games that use anti-cheat that is purposefully prevented from running on Linux/Deck, so I also have a windows handheld for those games (and the extra power helps for certain games and emulators too), but as there's talk of preventing kernel access anti cheat now, maybe Deck could play everything after that, so maybe I could just go Deck only in the future if they up the performance, which they likely will. I guess just game pass games would be the next reason to use a windows handheld, which I also wish would work on Deck natively.
I think their work on BC with their consoles have been great, but it seems they stopped investing in it unfortunately and I wonder if this would carry over to their next console. I wonder if they are going to open it up more to be closer to a PC, and "every PC" is essentially an Xbox to them too, think it would be an interesting move for them, may even spell the end for closed consoles at least, other than Nintendo who would probably still go that way. I can literally count the times I've used my Series X on one hand, everything I might have used it for I have it on PC anyway, I really see it as being nice as a way to play some exclusive 360 and X1 games at this point, so I do think they need to do something to keep their console more relevant and appealing next time, I think the handheld is one way they can for sure.