As much as I uh don't exactly enjoy the confrontational nature of Grudge's statements, he does have a point with a lot of BG3.
They did claim they started with the DnD5e ruleset and then made changes as needed, but it is clear they started with their DoS engine and ruleset and started to apply 5e to that, hence why many DoS mechanics still remain in BG3. Atleast with implementation, they did start with DoS, even if in planning they started with 5e.
And homebrew is very relevant because it is what Larian has done, it has homebrewed mechanics, and many of these homebrewed mechanics have become detrimental to the experience of players while others have been fun. I really don't like how they changed mage hand but I do like how they added just a little bit to weapons to give them a special action that is equivalent to asking the dm if you can swing your sword at the enemies' legs to trip them. Larian has to try to balance BG3 as a 5e game while still being fun as a videogame to someone who has no experience with 5e, which can be difficult. But genuinely closer to 5e sounds to me like it'll achieve both.