There was specific language that explicitly said "this is illegal" until the latest revision. Now, it's implicit, and in inquiries to the SEC they have repeatedly said "that goes against regulation".
The general idea behind rule 144 very sane: It's supposed to limit pump-and-dump IPOs and M&As, by forcing anyone who did not pay for their shares outright to wait 6 months before they can gain anything (and legally, the SEC is only interested in the overall guarantee - e.g. put options that guarantee you don't lose are AGAINST the current spirit and the former letter of the law).
However, the laws apply equally to someone who owns 90% of the shares (who is in a position to abuse an IPO and M&A) and 0.1% of the shares (who is likely an employee receiving RSU or options, has zero control, and likely not even any finances to draw upon)
The tax law is insane, the security regulations are complicated, and their interplay is ludicrously insanely crazy.
Whenever you see people saying "oh, it's very simple - you just didn't get the right advice" you can be sure that they have no idea what they are talking about - either they didn't have to deal with it, or they weren't aware they were doing something illegal.
