I always find being called an incel funny. oh no, you got me right in my internalized misogyny. The pain...
Due to the way psychological projection works, people's insults say a lot more about them than it does about you.
I am not saying that "if you call someone an incel, you are one". that is not necessarily the case.
Rather, people who use incel as an insult, it shows their twisted values place "having sex" as some sort of highest virtue. that in their mind, the most insulting thing you can call someone is "person who has no sex". And that this is also the lowest status a person can have in a group.
This is why jocks often insult other's physical ability and why academics insult other's mental deficiencies.
Because to them, physique or mental ability are the highest values on which a person must be judged.