To provide rewards commensurate with the extra logistics and time commitment that RBGs require. 2s esp. take very little time
He is glossing over the fact that weekly caps are what is causing the gear disparity problem. If you play an RBG, you get get more Conquest points for that win than an Arena win, which is fine. The additional points are the reward.
This question is specifically about the cap. As long as rating and format affect the cap, then players will never be able to catch up.
All they need is a season cap that increases weekly for all players. A season cap for all doesn't allow "instant" catch up either. If you start week 10(assume the cap increased by 2700 /week) and have to earn 27,000 cps, that's going to take you 150 Arena wins.
Is 150 Arena wins instant?