Difficulty of math

https://www.facebook.com/qiaochu/posts/10155226053470811?comment_id=10155226054835811&reply_comment_id=10155226905650811&comment_tracking=%7B%22tn%22%3A%22R7%22%7D

Terry Tao and Tim Gowers also talk about similar things.

https://jonahsinick.com/the-truth-about-mathematical-ability/