I'm sure he's building some sort of parachute for life after KF. He's obviously not going to do this forever so I'd imagine he has a plan.I honestly believe he's gonna kill himself after the site goes down for good one day, but he'll make sure to tell his paypigs that he's just gonna go teach English in China or something so they don't twig they've been had. Someone will try to put up a successor, but it'll probably fall apart due to infighting or some gay shit like that.
As far as what happens afterwards, CrunkLord is the only person who could hold it together and not be a total faggot about moderation. He's genuinely the only janny I respect because he's so against intervening with retarded behavior. Josh is moody and mercurial like a woman but Crunk was always superchill and generally has an attitude about not intervening unless the law is being broken. Who knows if he'd even want that burden though.
What would really have the chance to end the forum after Josh's departure would be all the parasocial losers who adore him. Without the weekly MATI firmware updates being loaded directly into their grey matter the sycophants are going to have a very difficult time learning to deal with forming their own opinions again.
As people's brains begin to heal there will be large amounts of flamewars and the various DM chain cliques gay-opping each other. But perhaps one of the Null clones will take power and the parasocial cycle will begin all over.