This is really interesting and I've been thinking about this a lot in the past few days and I've come to my own conclusion that a NGB is not necessary for airsoft.
It absolutely could be done, it's not rocket science. Parkour and Frisbee are established and recognised but then they've worked hard for that and really want to be seen as proper sports. Airsoft... doesn't really.
Firstly, and most importantly, is it an organised sport. Technically, yes, but it is, very much, a hobby first and a sport second.
Then there's necessity: we haven't had one and it's been fine. Why would one want a governing body and/or recognition by Sport England (or other national agency)? It seems this is mainly to 1) achieve consistency in national and international competition; 2) gain legitimacy for working with children and 3) secure lottery funding for "development". Competitive airsoft seems like a very small part of the hobby in the UK and I don't see any real international competitions and it's never going to be Olympic. Nobody seems that fussed about "bringing airsoft to the kids" (I know some people do try) and I don't think schools are very keen on guns 'n violence. Then, I don't see what funding would be used for if not for 1 or 2.
If the idea is to "lobby" government against new laws, then anybody can do that and organisations have previously been set up for that purpose. Plus, just because there is a governing body doesn't mean that the government would listen to them anyway.
Paintball is used to show what "could be" but ukpsf don't really seem up to the task either, no offence intended. I'd say they have more reason to be recognised but they're not quite there.
This seems like a bit of a storm in a teacup and has only come up because the temporary rules mean that we can't play with our toys just yet.