Excellent question. One solution for this would be to prohibit US-based first-parties from doing business with noncompliant third-parties (similar to what you p

Excellent question. One solution for this would be to prohibit US-based first-parties from doing business with noncompliant third-parties (similar to what you propose, but doesn't cut across different layers, so less messy, less potential for abuse). It is similar to how some other laws work, and it would be up to the FTC to make this rule.