No, we don't learn CSS because it sucks. I have given up on the idea that I will ever be able to remember all of the rules and exceptions.

Just one example most people already know. If I set a height or width on an inline element, it's ignored. So, obviously there is a limitation in the renderer that can't do it. But wait, make it inline-block and suddenly it works! So why the f*k didn't it just honor the width and height to begin with? It's quite literally a rule for the sake of having a rule.

I don't doubt there is some deep dark reason for why it is the way it is, like optimizations, or backwards compatability, but it doesn't matter to the end user. It's an implementation detail they shouldn't have to bother with.