There was a time when I would have completely agreed with you. I am not convinced by the flat earth argument but I have not spent time trying to understand how they reached those conclusions. It doesn't really feature as something worth spending my time on trying to understand at thus time but I also don't think they're dumb people. They are just different people I don't agree with. The impulse to call them dumb is very hard to resist but I have spent some time with "flat earthers" and they did not seem dumb to me. Maybe they're wrong or misguided but I would not call them dumb. After all, I hope to be able to have a conversation with them that might change their minds or mine but as soon as I see them all as dumb, that door is shut. That's just not worth it to me. But I totally understand why you would feel that way😀