Why do people assume bad people or people who said F up thing are bad in everyway?

Like for example if a man is misogynistic and say sexist things. People would automatically assume he is a racist. Just because he is misogynistic doesn't mean he is racist also.

Another example being a man being racist doesn't make him sexist.

Why do people feel the need to assume the worst of a bad person.

They assume if a person is negative in one way.They must be every thing under the sun.

A man said really sexist things about women. Which is terrible guys I know that. But people call him a racist incel. What does racism gotta do with this individual being sexist towards women.

Then then man had a YouTube channel talking about the recent police killing. He was disgusted by the cop killing. And was mad a black man got kill. So why do people feel the need to assume the worst of a person who says bad things. Just because he was sexist didn't make him racist. They made assumptions on him based on his views.

Like they assume incel,racism,homophobia,sexism are all treats every bad person can have all at once.

Note A bad person can be all those things. I know this. But also a bad person could not be all those things.