This is basically code golfed. You could always break up a regex into named variables of its constituent logical parts; same with FP.

This is kind of like calling js ugly because you could come up with a minified js script that is really complex and fits in one line, or if you inlined all function calls in a long C file into the main() function body. There's a sweet spot of the complexity density per LOC that humans are seemingly more-or-less tuned for, where it's often possible to get a computer to handle more complexity-dense code.

Personally, the shorter the code and the stronger the types, the faster I can tell if I made a mistake and the fewer places there are for me to make one, and that's why I like terse FP languages.