You know, I wish it wasn’t. Much of Amazon was on a version of Perl for years (and may still be) for almost all of their front end hosting. Facebook has transformed PHP into Hack (which is better for types, though technically not strongly typed), strongly suggesting they were running PHP until 2014. Let’s not forget what WordPress is still in PHP too.
I can’t speak for your managers, but my past managers didn’t need Agile to f things up. They can do that with anything!