That's exactly the argument for GDPR is. If an American megacorp doesn't want to respect the rights of non Americans then it shouldn't be allowed to profit at all from them. You can't just ban some and profit from the rest.
I think it's perfectly reasonable for non-American countries to impose laws on the tech businesses if they want to do business in those regions, but it's a dishonest characterization to suggest that what happens on a handful of American websites "determines what is appropriate", they don't have any such power.