Additionally, an ad hominem isn't actually an insult. They aren't the same thing at all.

An ad hominem means "You are wrong because of who you are." I.e. "You are wrong because you are an idiot."

An ad hominem is not just a general insult. "You are wrong because of XYZ and also you are an idiot." is not an ad hominem.

"Fuck you" also isn't an ad hominem or an argument, it is just an insult.

These guys don't even bother to understand the things they always accuse their opponents of doing.