I would chip in and say that remaking BG1 and 2 with 5e rules would blow. One of the main, but not the only, appeals of the progression through BG1->2->ToB is spellcaster progression with all is absurd unbalanced spells. Your ridiculous 15stoneskin-layers mirror-imaged blured spirit-armored fireshield red+blue 127% fire resistance mage chain casting PfMW and standing in the middle of a healing Fire-storm while everything melts around them is simply not possible in 5e imo. Part of the appeal of BG1 and 2 is the implementation of the 2e ruleset in all its absurdity - and then providing a bunch of late game encounter to match that ridiculousness.
You just need to compare how BG1+2 and IWD compare to IWD2 or NWN to see how a different ruleset will change the feel of the game, and how it is played, above and beyond the storyline. I don't think there is anythin to be gained in a BG1 and 2 remake with an inferior (in my opinion) rule-set.
New games, not remaking old games. I'm just pleased that someone (owlcat) is making "baldurs gate-like" cRPGs that are not 5e, to complement the 5e ones.
