You are correct, Balder's Gate 1 & 2 departed from turn-based D&D (although not the first). It was however still D&D.
As others have pointed out, having surfaces is not D&D at all...it is in fact a DOS mechanic. This and many more DOS mechanics changes combat radically.
Radically being defined as: Most of the rules are based of 5e, but these DOS contaminations make combat feel up to 85% DOS at times. In DOS you combated surfaces with other elements,ect. Do I need a cleric for the create water spell..erm..let's call it what it is...It's the rain spell.
Then there is the fact that the range on all spells and arrows is cut to a fraction of what they should be.
I wouldn't complain if this was just a new game, I would just appreciate it and learn the new mechanics. This however is not a DOS title this is a long awaited D&D title...that just isn't D&D.
I keep vocalizing, hoping that the Larian team will remember that in the past they have believed something to work, only to have to change it and listen to the fans.
Sooner is better than latter cost wise.
To be clear mixing DOS rules with D&D rules does not work for BG3.
The game has a great story and vision for story telling (even if it is biased to the dark side so far).
It has great graphics but a crap camera setup.
Loose the DOS mechanics and fix the camera and it will be awesome!
Now I see a sky once and a while...please let me pan up and zoom into first person. Getting rid the ability to meta game (by scrolling all over the place).