Regular expressions are more of a CS topic (regular languages), though common abbrevs of "re" and "regex" I've only seen in the wild pre and post my formal education in CS.
Yeah, I'd totally expect CS grads, old school Unix sysadmins, and Perl hackers to be fully familiar with Regex. Not so sure I'd expect that from bootcamp front end webdev "grads", self touch game devs, or maybe (I'm not sure?) engineers who have spent their careers in Microsoft dev environments.
