It's a numbers game. The longer they keep players in-game, the less crap Bungie takes from Activision. The season of the forge is one big time-gated time-suck designed with the purpose of keeping people doing as much of the existing content in new ways while infusing as little new content as possible. It's obvious what it is. On the other hand, no one is forcing anyone to play this content. I'm addicted to the grind, gosh darnit!