While BG3 is likely to be supported it seems that Larian is already moving forward on the next project. For example recent inverview on D&D channels, gives me strong vibes that Sven has moved on.

For reference check 11:38 and 43:45.



At a same time, recent Larian memeber did hint they might do something more BG3 related. We will see what they will do. But considering they don't seem to have anything in production, I wouldn't expect anything anytime soon.