Baldur's Gate 3 is the best isometric/old school CRPG ....
Except for that BG3 isn't old school in any way, shape or form. BG3 is an appearances-focused AAA game, and that is the proper yardstick by which it ought to be measured and compared with other games.
I certainly think it's a very old school game... and that is coming from someone who has played all of the old school CRPGs for the most part.
But if you want to view it that way - then that's cool.