Is it that big of a problem for people?
Her exclusivity? For a handful of people, yes.
I agree that the “evil” route is severely lacking in content. Sadly, in the game’s current state, it seems ideal for Larian to focus on the companions they have right now. There are a lot of issues the existing companions have (Wyll lacking depth, Halsin’s disappointing arc, etc.) and the effort they have to put in to add Nere as a proper companion with a complete backstory is no small amount.
This is why people have resorted to ask for Minthara to be recruitable in a good-aligned playthrough instead, it's just more easily done from a development standpoint.
