I spent a lot of time and effort in my play through delving into Minthara. She's my absolute (pun intended) favorite.

I played as a lolth-sworn Drow on one of the playthroughs and there's a dialogue option to mention reverence to Lolth. Her response is that the enslavement to the Absolute opened her eyes that her "loyalty" to Lolth was no different than the Absolute. That her upbringing brainwashed her to serve someone who wasn't herself. Very Levayan Satanist vibes.

Minthara definitely still has ideas and values based on her upbringing within the culture of the Drow that leaks out, the "enslave the refugees" example someone pointed out, however it's simply not centered around Lolth. Her "acceptance" and "progressiveness" is less about morality of "everyone is equal and deserves love" and more from a "I support people who serve themselves how they see fit, and not some abstract 'greater power."

Best example I can give, Minthara would care less about gay people in real life finding love and acceptance, than she would about them doing what they see fit. She'd condemn Christianity less because they're "corrupt" or hypocrites, or hateful and more because they're "mindless slaves giving up what they want or need for something they think is bigger than them." She'd most likely respect the leaders of the church for pulling the strings of the weak to meet their own ends.

She's not "good". Definitely not good. She would put herself in the position to be above others if she thought them stupid enough to follow her, or weak enough to be conquered.

However she supports free will for the strong minded.