It has shut down some but it mostly seems to issue nominal penalties.
For example, the EOS ICO unlawfully raised over $4 billion dollars. The SEC settled with them where they paid the SEC $24 million and the SEC agreed to take no further action.
The only lesson here is that if you're going to ignore the law and sell sketchy assets with over-hyped claims to unsophisticated investors in the US... make sure you raise enough that the cost for good attorneys few million to the SEC is just a rounding error.
Or the value is being transferred out of the US and toward other countries, because you can't even start an ICO in the US unless you have the right connections.