GV STI driver wouldn’t stop freakishly waving at me?

Just thought this was weird, but I was driving home from work (just finished a 12 hour shift as an iron-worker) and stopped at a red light still 30 minutes from my house. My wife won’t stop texting me (something about how I don’t treat her right or whatever LOL) so I take a look at my phone when I see a GV STI pull up to my side. Don’t think anything of it, when all of a sudden it looks like the guy is having a stroke waving at me. Practically a wacky-inflatable tube man just shaking his hand at me. Figured it was either a medical issue or maybe I had cut him off and he was raging, either way I didn’t wanna get near that. Not a big deal or anything, just figured Id share.