It's the players, not the playground.
Isn't the basic general premise of the current AvA arena the same as the WWI arenas ... dogfighting and not "Win the War" ?
I could be wrong, but isn't the AvA setup to pit like/equal allies/axis planes against each other in a "real" geographic setting and not to capture bases to reset the map ? ... so if the playgrounds are similar in their basic intent then why aren't there as many people in AvA (past and present) as there has been in the WWI arenas since they have opened ? ... my guess (I know it's a stretch) ... it's something
NEW and when the shine wears off the exterior ... well look at AvA.
I believe that once the newness of the WWI airplanes wears off ... it will be a ghost town for the most part ... just like AvA ... and that would be a shame.
I don't think for one second that Dale and Doug believe that the WWI participation will keep up at the pace that they are seeing, for an extended period of time, keeping it status quo.