Actual UML-according-to-some-books is old and unpopular now. I think C4 is taking its place, in that I've seen architect-types ask for it. More generally, I really like PlantUML and the prettier-looking Mermaid which both allow me to code diagrams using a text document.

Yeah, I agree: academia gets people expecting to go, "give me 2x Visitor Pattern, then 1 Builder Pattern, then as many Divide and Conquers as you need to reach the end". It can be nice to have a name for things, but most of the time I'm asking for, "see how the setup, actual work, and cleanup are nicely divided up? Do like that." Or, "let's put all the related endpoints in the same file."