For me, it's enough for them to remove the '3' from the title and add a subtitle.
If the only connection(s) this game will have to BG1/2 are whatever lingering effects of the time of Bhaalspawn saga (100 years prior to this), or a few non-human NPCs, a name drop or two or what have you....then the game doesn't need (or deserve) the '3'. It only really needs it if it is in some fashion carrying on the narrative of the Bhaalspawn saga (which, far as I understand, it is not). Thematic similarities do not justify it being claimed as a sequel.
The Baldur's Gate: Dark Alliance games existed and the world didn't fall down. This is certainly more akin to BG1/2 than those games were, but it's still not part of that story. Using the name works for me, but that '3' is the stone around its neck for many.
Will it stop me from buying it upon final release? No. It's still a D&D 5e based single-player game. Something I'd like to play (since Sword Coast Legends spectacularly failed to deliver that and I've been waiting since Neverwinter Nights 2 for another D&D rules based single player game).
To me, this is not Baldur's Gate 3. This is Baldur's Gate: Something Else.
