Media regulations do exist, and are more robust outside the United States. Usually the answer to your question about bloggers and YouTube personalities is that they are ignored by the regulators of the professional media, but may attract police attention in extreme cases under anti-vilification laws that would likely be unconstitutional in the U.S., eg. https://en.wikipedia.org/wiki/Mark_Meechan (UK), https://en.wikipedia.org/wiki/Blair_Cottrell (AU).

I don't see the problem with subjecting foreign media to the same or even stricter laws. Yes, it's difficult to enforce the law against foreign nations, especially your friends, so enforcement often doesn't happen. That doesn't mean that foreign meddling ought to be made legal, which would be a step backwards in view of laws like the https://en.wikipedia.org/wiki/Countering_Foreign_Propaganda_....