I've been listening to Aquired recently (podcast about company origin stories) and when talking about privately owned companies (for instance, the recently Mars Inc. episode) they always do back of napkin estimated earnings because the company is private, which apparantly means they don't have to disclose earnings.

But in my country, Denmark, every company earning above 50.000 DKK (=7853 USD) has to disclose earnings. I believe this is for price discovery purposes, so that other entrepreneurs can see how much margin companies have and try to compete if they earn too much money, which is an important part of capitalism, right?

How come this is not required in USA, the "home" of capitalism? If I'm not mistaken of course, my apologies if so.