I "make it my personality" because there are people insisting a Nazi salute is a stim. I might act, talk, and think differently, and I might flee from bright lights like a vampire at high noon in Pheonix, but I sure as shit don't throw Nazi signs.
I do it because people seem to think autism means I'm stupid. Even people who thought I was smart before they knew.
I do it because somehow "I'm just not up for socializing" or "I'm focused on something" doesn't cut it to decline an sctivity.