I thought that same thing.

Besides, it wasn't liking a particular _language_ they took as a bad sign, it was _functional programming_.

If you like functional programming, and you encounter a candidate who also likes it, and you consider that a red flag ... that seems highly irrational and inconsistent.

(Not trying to sound combative. I appreciate the original post! Just being candid about something that sounds odd to me).

Edit: I would bet there's more context that was out of scope for the original post. I would not be surprised if it were much more than just "liking functional programming." If someone is overly zealous to the point where you might wonder if they'd start an uprising or storm off in a rage if asked to do anything other than functional programming (or anything else for that matter), that would be a red flag.