I'm thinking that, with Kawhi likely hitting FA two summers from now, he's looking hard at the Spurs roster and realizing that, with an aging group of Parker, Manu, etc., and if they can't land another star FA (like a Lebron, or George, etc.), it's unlikely SAS stays in bonafide contention for long. Obviously with Pop, anything is possible, but he's (Kawhi) keeping his options open. Remember, it's not just the Rockets and Warriors, but up-and-coming teams like the Wolves, Pelicans (who could give them some trouble w/their size), etc. Oh, and the Thunder.
Still think there's less than a 5% chance he gets traded, but could he demand out this summer if Spurs have a somewhat lackluster playoffs and it doesn't seem they can land another star FA? Possibly.