Overseas operators? Nonsense.
I know US people who do this for a living
Literally the example in the comment I replied to was an overseas operator. But my point is even if you did go after spam operators, alternatives will simply pop up in other jurisdictions, as has happened with literally every other form of spam.
Technically this is something the FTC could get involved in as it's illegal to advertise without making it clear you are.
A few years back a bunch of influencers were fined for doing just that.