I wouldnt paint this so cut and dry. I will agree that they will not retroactively enforce this; that is making a list of participants and going after them (would be really difficult, to be honest). But you are running afoul of some pre established law by participating in these as a guidance has been issued. Since you aren't the one holding the money; they would be more likely to go after the ICO (this is about money, after all). Besides willfully purchasing an illegal, unregulated security, most of us are not accredited investors, which requires an AMAZING amount of income or wealth to qualify for. Only accredited investors would be allowed by the SEC to participate in something with this much risk. If you lie about being an accredited investor, or your region, to participate in one of these (they are starting to ask this now), you may forfeit your ability to seek damages/redress as you committed fraud.
Be careful. All of these arent securities, but for the ones that are, treat these as truly risky/volatile investments.
"In the United States, to be considered an accredited investor, one must have a net worth of at least $1,000,000, excluding the value of one's primary residence, or have income at least $200,000 each year for the last two years (or $300,000 combined income if married) and have the expectation to make the same amount this year."
If you don't have a lot of money, you can't be liable for not applying to be an accredited investor. Just don't lie and say you are.
This is a major problem in the USA. The laws for accredited investing are there to protect people that previously couldn't even look into investments. It's all pre-information age. It's archaic, old, bullshit. The problem came from supposedly "creditable" people claiming it was safe to give them money, not the other way around. This is an ancient statute that needs to be turned to rubble. One of the biggest values in cryptos today is that the average person can choose to have some autonomy with it.
But please, continue to roll over and keep the status quo. We all know that's why everyone became interested in Bitcoin to begin with.