I suspect it’s the opposite way around: most people, when they hear “git”, macroexpand it to “github” and don’t even know that there is a (more powerful) command-line interface.
The peer-peer distributed nature is barely known — these days it’s a centralized client/server system. I remember the Internet connection going out at work a few years ago and developers saying they couldn’t coordinate bc github was not accessible when they could easily have synced, merged etc with each other directly.
My partner definitely does not know the difference between Git and GitHub. He's not much of a programmer but yeah.. maybe this is like Java vs JS all over again. Or jQuery vs JS. That one makes me extra sad.