The way to recognise UML is by the wide variety of arrow styles that nobody can remember. I'm 90% sure that's the main reason it didn't catch on.
You have to learn UML because of the stupid arrows. Compare it to something like this which acknowledges the fact that nobody is going to casually memorise 10 different styles of arrow just to read occasional UML diagrams:
Different arrows are useful to express different relationships. But perhaps you should just put a legend next to each diagram, or use words to annotate your arrows?
No one forces you to use all possible arrows, you can learn just one, and use that.
When reading a diagram, ideally you would read it by looking at the generated diagram, not text, as that's the entire point, but even when reading the raw text, it's apparent where the arrows are, based on "less than" and "greater than" characters, no?
You have to learn UML because of the stupid arrows. Compare it to something like this which acknowledges the fact that nobody is going to casually memorise 10 different styles of arrow just to read occasional UML diagrams:
https://buck2.build/docs/concepts/concept_map/
Much better.