The other reasoning I've seen - take it for what it's worth - is that the ban came down because a bunch of Joes couldn't distinguish between Magpul polymer magazines (GTG) and, say, Tapco polymer magazines (crap). The intent, therefore, was to keep
all polymer mags out of theatre so people wouldn't be using sub-standard/unreliable gear in combat.
Hadn't heard about the lawsuit, but now that it's been brought up, I find general officer spite an equally plausible explanation.
- C.