this is obviously not a clear line. No money is exchanged when I promote my own product through my own channels, nor when I promote my friends products, whether I disclose it as promotion, or disguise it as my genuine unaffiliated opinion. Sometimes it really is a genuine opinion! Even worse: sometimes a genuine opinion becomes an incentivized one later on as someone's audience grows
the good news is there is a solution that doesn't require playing these cat & mouse games and top down authority deciding what is allowed speech: you want better ways to reach the people who want your product.
Ads are a bad solution to a genuine problem in society. They will persist as long as the problem exists. People who sell things need ways to find buyers. Solve the root problem of discernment rather than punishing everyone indiscriminately