Ruin Explorer
Legend
1) Definitely don't buy an Xbox. Microsoft have openly stated they're moving away from having any exclusives for it, because they conclusively lost the console war this generation, and are likely to lose it next generation (if they even compete, though I imagine they will). Whereas the PS5 has a ton of exclusives, including stuff that was (and still is) exclusive to the PS4.
If you're considering getting an actual console, go with PS5 or PS5 Pro (depending on budget).
2) Steam Deck vs Switch/Switch 2 is a very different choice.
They're relatively similarly priced - get the OLED models of Steam Deck or Switch 1 if you get them (they're just better, including in ways beyond the OLED screen) - but with Steam Deck, you can play most of the games you have on Steam, and kind of shockingly well in most cases. So you have an existing, and probably significant library - whether it's games you actually want to play on portable is a different question. With either Switch, you're going to have to build up a library from scratch, and Nintendo generally doesn't do sales much, and when they do do sales, they tend to be fairly pathetic discounts. On the other hand it's literally the only (legal) way to play Nintendo exclusive games, of which there are large numbers, and they tend to be good - if you're into that sort of thing. I would suggest looking into Switch exclusives if that's potentially of interest - there's a lot of Zelda, Mario, Fire Emblem, Animal Crossing, Smash Bros etc. that isn't available elsewhere. Switch 2 is going to be a little more expensive and realistically, is going to be a PITA to actually buy this year. Also the games will be more expensive. On the other hand, it's pretty powerful, and has some cool exclusives and so on.
Does she game at all or is willing to try games at all? If so, I'd lean towards the Switch or Switch 2 because it's both good as a handheld, and good as a thing plugged into the TV for multiplayer games, and has a lot of friendly/fun co-op games and so on.
If not, certainly most price-effective one is likely to be the Steam Deck - it's not amazingly powerful or anything, but a lot of games have custom settings for it, and thus even some recent AAAs have 30-40 FPS on it, with those settings.
