> I still have no idea what the option key is for
It's for "⌥".
Yes, that's not ideal, and it's a striking UX failure on Apple's part that the keycap says "option" while the menu says ⌥ - all the more striking given Apple's generally well deserved reputation for getting that kind of thing right.
Same goes for control and ^ - granted, Unices have represented Control as ^ since forever, but part of the appeal of a Mac is supposed to be that you don't have to be a grizzled hacker to understand it.
That said, how does it take (more than) a decade to learn these correspondences? Not that I don't understand your complaint here, and I agree it should be fixed, but...I mean, this stuff doesn't seem all that hard.