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.
Ironically, from the posts I have seen. The people that have little to no 5E experience are enjoying the game a lot, and the people that are knowledgeable in 5e are the people with the problems. People that don't have 5e experience see this as a dungeons and dragons game, with good story telling, and do not get hung up on translations of rules. While the hardcore 5e crowd are the ones that seem to despise the game and go on about Solasta being so great.
Just thought this sentence was slightly off.
Well for me that means it is completely on the other side of the balance. For those who do not play 5e a lot, this feels like how they perceive dnd and is fun. They have achieved that side. But for those who were promised a dnd 5e game it feels very far from core dnd, and they start to notice mechanical changes that seem detrimental and therefor unfun to them. In making a game like this, you want to balance the interests of both kinds of groups, fans of the series you are adapting AND new players. I personally think moving closer to 5e will still allow them room to keep new players invested in the fun mechanics (for example the Weapon abilities, and to a more limited extent surfaces and barrels if they get toned back) while pleasing the 5e crowd. That and a lot of the cooler stuff 5e has to offer kinda depends ON certain 5e mechanics being intact, like paladins smiting or warlock familiars scouting and giving advantage.
Funnily, I think they would have had an easier time adapting 4e due to how 4e combat was constructed (and with that though I will lament that I won't get to the crazy summoning shenanigans I get in my 4e game...)