>Lots of people have seemingly irrationally strong attachments to their hometowns

Nobody with a modicum of intelligence thinks that is irrational. Of course people are going to have strong attachments to a place where they spent a major portion of their childhood making memories and relationships.

The only seemingly irrational thing would be indifference. You don't spend 18 years in a place and not have any emotional reaction to it (good or bad).

I thought it was pretty clear that the implied irrational part of it is the opportunity cost of choosing your hometown, not the actual attachment itself.

If I'm a brilliant mathematician or a world-class athlete and I choose Kansas over Cambridge/Boston, then yeah, plenty of people are going to think that my attachment to Kansas is making me act irrationally. I don't think they lack a "modicum of intelligence" because of that thought.

There are obviously exceptions where your choice of location doesn't matter, but if you're a high performer then it frequently does (with the obvious notable exceptions e.g. Prince).

[EDIT: I originally just had a quip about not being a sports fan, but I thought you deserved a real reply.]

As a mathematician by training, I would venture to say that there are probably few mathematicians who are able to choose a location first and then a suitable job in academia or industry (in academia, that number is almost surely zero).

In particular, if you're an academic mathematician and you ended up in Kansas, then that probably means that you're working at the University of Kansas or Kansas State University.

Or Garnett (Minnesota). Not his hometown, but longest place of residence.

Also, Buffet, Prince, Eminem, etc. You can find an argument about a lot of places. The fact that people write of (any) place without spending any amounts of time there, speaks more about them than the place they're referencing.