I think he'll retire because I get the impression that the fire and passion is waning. He has nothing left to prove and is financially set. Also, being a professional bodybuilder is not an easy life. The diet (both bulking and cutting) alone can wear thin. And the constant daily training and being a human pin cushion can't be fun. Then there's the toll it takes on your body and health. It would be nice just to live a normal life where you can eat like a normal person and just train for the enjoyment of it without all the pressure. I don't think Jay is like Ronnie where he likes walking around at 300lbs and throwing tons of weights around.
I see Jay just settling down raising a family and being a successful business man. He seem like a smart down to earth guy with the ability to keep things in perspective.
Maybe you're right, I just always think of 2002 when everyone said Ronnie was gonna retire, then he did the opposite and came in more dominant than ever for 3 more years. With Vic out this year I reckon Jay's got it in the bag, and most champions want as many titles as they can get, but like you say he's not a passionate powerlifting behemoth like Ronnie sow who knows.