If these scams and frauds are being fueled and legitimised by the venture capitalists, and the venture capitalists are US regulated, shouldn't the regulators be

If these scams and frauds are being fueled and legitimised by the venture capitalists, and the venture capitalists are US regulated, shouldn't the regulators be going after the venture capitalists? Even a few seconds of amateur due diligence (e.g. the time it takes to read "20% guaranteed annual return with zero risk") would have set off alarm bells, so they must have known they were aiding and abetting criminal activity.