If we accept that zodiac signs affect our nature...

... then is one responsible for the negative aspects of their nature?

For example, I just read that schizoaffective disorder is more likely to happen to someone "born during the winter months":

https://www.drugs.com/cg/schizoaffective-disorder.html

So we have physical proof that some zodiac signs are more prone to mental disorders.

Is it fair, then, to hold someone responsible for acting in a way that is natural for their sign, even if that way is not socially acceptable? For example, judging a Scorpio for being promiscuous, or a Capricorn for dating a man for his money.

This stems from someone's earlier comment that many Virgos are prone to cheat and feel no remorse about it, which may actually be true. But does it make them a bad person, if Virgos are naturally prone to do that? Had the exact same person been born a few months earlier or later, they may not have that inclination, and would thus not be a "bad person", right?

If a psychotic really isn't responsible for their psychosis, or an alcoholic for their alcoholism, is it fair to judge others for their natural shortcomings?

Yeah that defense would only fly in Firebunny's mental court.