I did well in Physics in High School, and my instructor was massively interested in Astronomy, but he taught us very little about it.

What do you mean by fundamental here? For studying astronomy at an university? Then yes, agreed, but I am wondering about the very basic understanding of the principles at all, are you implying that kids today don't learn this anymore? You know, what our solar system is, what the earth is, and it's, well, shape..

Or at least don't do it in such a dismissive way.

You think this is equivalent to knowing about the Milky Way? You seem to have put some major significance on something that really has very little baring on our day to day lives. Im sure most countries teach a good deal about the solar system and the planets, It's taught at a very young age in the UK and its refined through the years of school to the point where you should have a good understanding of it all. But we never put any emphasis on this. You know why? Its irrelevant at that level. Unless you are studying for a degree or even higher this won't have any baring on what you are learning.

The Milky Way is a candy bar, everyone knows that!

By your nick, I'm not surprised you know about Milankovitch cycles.