Well, blame WoTC for all of this. There is probably even no one to work with there at this point. The whole team, that Larian cooperated with, is long gone now, which doesn't inspire confidence for future projects.
I think it's frankly far fetched that WotC is the reason. If anything I could see WotC being willing to write a blank cheque for Larian to do "w/e" for Baldur's Gate 4 given how well received 3 was. It's much more likely they just want to do something else instead and the split was amicable.
