Neverwinter Nights 2 OC, Mask of the Betrayer and Mysteries of Westgate and some of the Bioware games handled evil quite well so it's not a cRPG issue imo.
I think the issue is that there's too much focus on the good path and a mistake in demographics. Apparently Larian thinks people playing evil are few and those that do are all chaotic evil male players.
Mask of the Betrayer had an amazing "corrupted by power" evil route. BG3 is flopping hard by comparison.
I'm in the middle of the evil route with my gith wizardess and I'm not sure whether to continue. At this point a) the druids have nothing to offer (she already learned from the hag about the netherese magic, what would a druid know about it?), b) the goblins bring nothing interesting to the table, and c) Minthara seems yet another female drow obsessed with her goddess, which is typical for them, but she has nothing substantial for the PC either.
Frankly, the most promising offer so far seemed to be the hag. But of course that was a red herring.