Lack of evidence and testimony is what I've heard.

Probably because his political handlers own him as a useful tool asset at least until the statute of limitations lapse on his alleged crimes kompromat

Because he didn't traffic children.

If you look at the charges of Greenberg and that essentially nobody once ever referred to Gaetz as a suspect but rather "subject of" or "involved in" it becomes pretty clear what happened.

Greenberg was running a blackmail ring, or at least managing it, Matt Gaetz was the target of it. He started getting suspicious and went to the FBI.

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