I'm actually glad Larian is looking to adapt the 5e system. 5e simply doesn't fit perfectly into video games
People talk about 5E being a system perfectly balanced over 5 years - but the truth is, the game never has had a proper "patch". The PHB was printed at the beginning of 5E and stayed the same. Aside from a few minor line changes in Erratas, all the fixes are built in supplementary material, which BG3 won't be implementing.
I don't mind adjustments to the combat system because in PnP you're used to controlling 1 character, whereas here you control multiple in most games.
I also accept the fact that 5E PnP is played in ironman mode, which alters the way encounters are designed (pnp encounters are inherently easier since there's no reloading).
My larger issue is that while I'm happy for Larian to be playing with the combat system, they really aren't taking advantage of the EA to push out quick iterations, and let the fan base try and feedback on different things. The only combat related change I think we've received due to EA feedback has been surfaces. It's already been months since the release - realistically we could've tested multiple system by this time.