It needs to be accepted as currency to be useful.
My friend uses it to anonymously buy servers. Their country has a history of killing political activists so they take their privacy seriously when it comes to that kind of thing.
I would say Monero was useful to them, at that time. It didn’t have to be mainstream to be useful. They weren’t investing in it. It allowed them to make an international transaction which is much harder to track than other accepted payment methods.
For what it’s worth, I’m very familiar with that feeling too, despite excelling academically and a high score on IQ tests. Ignorance is not a lack of intelligence, it’s more likely a lack of experience. And every culture, job and hobby will have their own terminology and assumed knowledge, so not even the Einsteins could pretend to already know it all.
I listen to music all the time, I’ve composed amateur music myself, and enjoy occasionally reading wikipedia for trivia of music theory, but if two musicians start talking about basic stuff like major and minor chords I’m already out of my depth. Do I do the smart thing and ask them to explain? Or do I just nod until they talk about something I know, or tell myself I don’t actually care about music theory?