I think a lot of people that get wrapped up in flat earth stuff aren't the smartest, and so the problem starts in school when they are taught things like trigonometry, they often have a bad/dismissive attitude towards it (thinking "when would I ever use this in real life") or they just can't do it.

As an example, I have a friend that dropped out of high school relatively early to do a trade, and now he is keen about science and watches many videos on space and the like. One time he was theorising to me about how electricity in a wire makes a magnetic field, and that if you put it near a magnet then it would move. I said, that's what an electric motor is, lol. He probably would have learned that if he did better and stayed in school longer, but he wasn't interested back then.

But at the other end of the spectrum, the first person I really heard about flat earth from happened to be someone I went to highschool with. This was at our 10 year reunion (and was nearly 10 years ago now), and he had gone on to become a geologist, but had recently jumped onto flat earth. So, it's quite mind boggling to think about what was going on in his life that lead to that conclusion.

And 1 more thing about learning, I don't recall any schooling regarding 3D space, like how to think about it, approach it, etc. And then when talking about viewing/measuring space from the perspective of earth, you also have to consider your position on the globe, and how that relates to other objects. Even now I struggle with this aspect, and my job for nearly 20 years has involved 3D modelling on computers (although my work is 3D, it is all "planar" though, which is different to bodies in space).