I learned UML in university, in 2018/19. Nobody liked it, but it made for a practical way for professors to give us class definitions in a language-agnostic way. All the classes about learning to use UML were otherwise universally hated (because not giving us the class definitions in UML was thus vague) and besides toying with a UML to java converter once, i've never touched it again and i don't think any of my classmates have either.
Wow, I'm surprised they're still teaching it! I learned it in university in 2007 or so and found it utterly useless and outdated even back then. I don't think I've ever seen it used outside that class.
I teach OOP at a large reputable university, and I use UML every step of the way. For all the hate it gets, it's still the best thing for documenting and describing relationships in OO systems.
