The more that BG3 followed the DnD rule set, the better it became. Most of the issues I have with the game design are holdovers from DOS2 or other deviations from DnD. I also think that Larian benefited hugely from the Forgotten Realms lore and world building, which is so much better than DOS.

Without the DnD and Forgotten Realms IP, I doubt this would have been much more successful than DOS2.