I saw this in an article about the Xbox-s that mentioned the Steam Deck
Larian Studios head of publishing Michael Douse said that playing it on the handheld(Steam Deck) is "absolutely wild" and that, while it won't be verified on launch, the team is actively working towards it. This is a unique approach. Rather than developing for each console simultaneously, Larian Studios is rolling out Baldur's Gate 3 when it's ready for each. First, it'll arrive on PC, then PS5, and then Xbox or the Steam Deck--whichever comes first. While the wait might be longer, it saves the game from being delayed across the board.