An ethical moratorium doesn't outlaw the tech outright, but it does influence sources of funding, availability of laboratory facilities and capital, and the diversity of personnel willing to advance the state of the art.

It would be similar to the impact that an executive order by G.W.Bush had on stem cell research in the U.S. It was delayed by a few years, and some research moved overseas, but then the issue largely became moot when the tech progressed past the need for embryo harvesting.

At most, this would slow down gene mod tech for a few years, as the pressure in the djinn bottle builds. As long as we don't annihilate our civilization, it is practically inevitable that every human will one day have ready access to cheap gene mod tech, in the same way that they now have ready access to networked computer resources.

The only way to reasonably keep this tech out of the hands of the irresponsible public is to convince scientists to not develop it in the first place. And that's what this is. I question the motive behind the suggestion, but that's my foil hat talking.