This is entirely made up? Most people are totally fine with speed limits being what they are and don't say anything about it.

Oh, that explains the massive difference in speed limits from one country to another then, especially if they're next door neighbors.

i don't see what that has to do with it

In the sense that they don't care what the sign says when it comes to their own driving? Sure.

no, in the sense that they just follow whatever the rules are and don't care very much, or mildly break them as is convenient and still don't care very much

That's because they are slowpokes and maniacs: In a decently flowing road, the majority of distinct cars you see are either moving significantly faster or slower than you (and the more extreme the difference the more likely you are to see them). Of cars that go at a similar speed to you, they approach you / you approach them more slowly so you'll see fewer of them.