When I first encountered the Haskell Parsec library, the beauty of parser combinators hit me and I felt I'd never have to write a regular expression again.

This hasn't been the case because I had to work in other languages where usage of regexes was more idiomatic/commonly understood. Parser combinators are great but most of the time, the problem can easily be solved using a regex and we can't really justify adding yet another library in the dependencies for the rare case it would be better suited.

In addition to all the benefits they can provide in terms or readability, re-usability and abstraction, parser combinators can even compete with regexes in terms of performance. https://pl-rants.net/posts/regexes-and-combinators/