It’s possibly as simple as it being part of recitation when kids learned the solar system’s planets and now it’s just not. Some folks have a real hard time wrapping their head around the idea that a ‘fact’ they learned and knew their whole life has been decided changed. Or maybe that isn’t it. I dunno. My concern for Pluto is mostly just for shitpost value. I don’t really give a rip whether it can clear its own orbit or not.