I agree, it ought to be a hard line.

Question is, though, where's the line? We don't all come with the same exact moral compass, and we're all perfectly capable of rationalizing evil, so you can't just say "be a moral and non-bigoted person" and expect the desired outcome. Plenty of slave owners worldwide were convinced that slavery was not just morally admissible but even admirable.

No matter where that line is, it needs to be well-defined and agreed-upon, or else it's arbitrary, and thus open to abuse and corruption by demagogues.