This is true because

Devout ?x aficionados tend to be a little... opinionated.

I've met plenty of devout Prolog, C, C++, and Java aficionados, and yes, they're opinionated.

Also, you're more likely to notice opinions that differ from your own than ones you agree with, these are more likely to be held by groups you don't belong to, and you're less likely to belong to minority groups, such as Lisp programmers.