I noticed similar a while back. ONE person in EWA, that's it. Apparently the idea proves to fail due to many choosing the latest, easiest rides/arenas, and not interested in diversity or challenge.
I don't think that's the problem.. Sure there are many that can't fly anything but late war rides, but there are many that fly other stuff in the MA's. Hell I flew almost a whole tour in the Huri 1 a few tours back, I also fly P40's pretty often. The problem with EW, MW and AvA is just the lack of players.
If there isn't many people in there, no new people will join, it's like a self feeding problem. I flew in MW yesterday and tried some today, but there simply aren't many fights to be had. Sure you don't need 400 people in the arena but IMO it's tough to find quick fights with 30 to 50 people in there if you are lucky. The other thing is, even in MW half the cons I see in there are Huri 2's, A6m2's and Spit 9's. Those are all just as easy and dweeby as any of the LW rides, so claiming it's because of LW aircraft not being there isn't correct.