I wasn't into DnD before this game got announced but if true, that seems like a very sad development. Then again, what is stopping Larian from enacting their own 'homebrew' rules for this game? Isn't that very much the spirit of DnD?
Legal agreements
That doesn't really make much sense to me. It's not like Larian is breaking any written rules by supporting that playstyle. It's just extra flavour that is in line with the lore as presented in the Sword Coast Adventurer's Guide.