Good eye and good question!

When I first joined, the existing codebase was already built out in PHP on a LAMP stack. I was really opposed to it at first but I've learned to love it since. The safety, speed, and size of a compiled language on the web is something most modern frameworks can't compete with.

I, personally, have built a ton of in-house APIs here aiming to "modernise" php and am really proud of the outcome. It's nowhere as safe, readable, or dynamic as something like a Rust or Swift but PHP is definitely a strong competitor for the modern web (IMO).

This article https://mcfunley.com/choose-boring-technology also really helped me come around early on.