The game has moved to catering to single players and small groups only. The backlash they would get from making anything new FC only would be huge. Personally, I wish they would because there seems to be little reason to join a FC unless you just want some social interaction. You can get the FC buffs from your squad and the airship/submarine rarely bring in items that can be enjoyed by the FC in general. It's a weird system and considering the track record the devs have I doubt they are going to make anything FC exclusive.