Math vs. Math Education. That’s a huge difference! The first is usually a near genius who can’t relate to other people but can solve equations in his head and dreams in five dimensional space. The other is an illiterate communist who’s unable to hold down any job but found a refuge in academia and has burrowed deep into the system, championing every teaching fad and folly.
I greatly prefer the first group, though my recollection of them is they were incredibly strange when I was in school in the early 70s. Likable enough, though. On a completely differently wavelength. Totally engulfed in their subject matter, which was an abstraction.