I think that’s kind of far fetched and unfair to treat Larian as if the existence of BG3 is solely some scheme for them to rake in money using the dnd title. They wouldn’t have made the game if they didn’t WANT to make the game for a genuine reason.
Well there was this quote from Sven I found awhile ago, which at the very least, suggests the BG IP was chosen just for market recognition. And the game's release hasn't really disproven that either.