For me, it isn't because I hate the Prius (I don't), I just found the Prius repellent memes to be pretty funny. I definitely don't support actually rolling coal on other cars though.
Well, I just chose my username based on my profile picture (except for my first username). The name I have currently is based off the character "Hayaku The Cricket" from a Netflix show.
I based mine off of my YouTube channel with the same profile picture and everything. I got the name M Racing from the first letter of my first name, and the fact that I love racing games.