You guys wanna see something really terrible, search "BG3 voice actors" on Youtube and watch how many videos completely forgot to include Minthara. Fun fact; I still haven't found a single one which includes the character or her actress, but naturally Halsin is included in pretty much every single one.
Is he more interesting than Minthara? Nope. Is he more unique than Minthara? NOPE. That's what happens when you make a lackluster evil playthrough and lock a companion behind it. Imagine putting all that wonnderful work into bringing your character to life and people not even registering your character exists because 0.01% of the population will actually give up on 4 companions and meaningful content from all the tiefling NPCs for a chance to meet the intricate Nightwarden.
Imagine if in Star Wars Knights Of The Old Republic 2, the amazing Visas Marr was locked only to the Dark Side players. Imagine missing out on such an awesome character with one of the best backstories and epilogues in the game because of some arbitrary thing like "EVIL PLAYTHROUGH". Anyone who played KOTOR 2 knows very well how mindblowing it was turning Visas Marr back into a Jedi after everything she went through.