Non race sails will probably never have "mast over cambers" rigging. It takes a large luff sleeve for it to work, which will NOT be popular with recreational sailors. You don't want to drop these sails in the water for long since the luff holds A LOT of water.
They are more expensive to make, which again will not be popular with the average sailor.
I am not saying that Gaastra can't do better with the GTX rigging, they probably can. I also can't believe that rigging a two cam sail is that difficult. An extra minute over a no cam sail? I can live with that. I had a GTX 6.5 for several years and it was no big deal to rig. I guess the new ones aren't as user friendly.