Has anyone even questioned the legality of it? Even if they did, the political will in this country won't back overturning it. I could easily see the POTUS rolling the dice on this one too
It is an interesting question based on the current climate in Washington.
If an EO was issued that was not technically an outright AWB, but a set of very restrictive regulations would there be enough people motivated to challenge it? Yes, obviously there would be some, but many are more motivated right now to seem more conciliatory in the eyes of the public. Even though most people support the 2A I could see groups manipulating public opinion to the point that even many pro 2A politicians feel the best strategy might be to just let something like this go.