Joubert dismissed Buttle's programs at Worlds as not having any "great difficulty", so clearly he doesn't consider Jeff to be his equal as a skater. Brian made no mention of the in-between stuff (that was Buttle and Weir's rebuttal to his argument) as to why he deserved to be the winner; he focused solely on the quad. By his own limited definition of what makes a good athlete, Bradley trumped him in the SP at TEB.
No Joubert doesn't consider Buttle his equal because Buttle doesn't have the quad. But what makes you think he considers Bradley his equal. And who says Joubert only cares about the quad? That's not true and unfair... He has massively improved his spins, his footwork, and his artsitry in the past couple of years. IF Joubert didn't think those things were important, he would not have done those things.
He just thinks the quad isn't rewarded enough in this system. Joubert felt (Lambiel, Daisuke, and himself were in a different class than the rest if I can guess) He didn't think Buttle without the quad, is in that group. But it doesn't mean he thinks that Bradley with his poor skating skill deserves to be in the top class either.