I think it would've been fairly easy for readers at the time to say "the monster's a murderer, that's the story." It's easy for others to say the monster's a victim and not responsible for his actions. We see the two points of view throughout this comments. The comparison to an incel is almost silly, though. "Man decides women are The Problem and becomes dangerous" is different from "Man is abandoned and feared by his only parent at birth, he has the impulse control of a small child (recall he was literally just born) and he has the body of a very large adult man." He even does try to be good, but is angered by people dehumanizing him for his appearance. (Dehumanizing people based on things they have no control over: sound familiar?) But then there's the important bit: this does not absolve his crimes! He is, in fact, a murderer. But the people who hated him also bear responsibility. Most of all his parent who did no rearing, teaching, or literally anything but screaming and running bears responsibility. Is he a killer? Yes! Is he a victim? Yes! Is Victor responsible for everything? Also, yes! The people who rejected him responsible? Less so, but yes!