Guilt by Association
The Fallacy
Saying an idea is bad just because a bad person happens to like it too.
Why it's wrong
Even bad people sometimes like normal things, like drinking water or breathing air. That doesn't make water bad.
Example
The evil villain in the movie likes eating apples. So if you eat an apple, you must be an evil villain too!
What the Fallacy?! (ELI5 Edition)