I don't think this is the case. I think Saban wants the challenge. He jumped from Mich St to LSU - a step up in competition year in and year out. He jumped from LSU to the NFL - a step up to see if you can perform at the highest level....he couldn't. So, in returning to college ranks, where did he go? Alabama. A school with some of the highest expectations on a program, but also the resources to achieve that level of success. He came back to the toughest conference, to a program that will accept nothing less than another NC every year or two, and has for the most part been successful.
I think he's having a bit of a down year, which is bound to happen to everyone, but he'll still end up with 9-11 wins. He'll still keep AL at the top of the SC discussions and mentioned in the CFP year after year. The fact that JMac, one off his own tree, is taking talent from his state isn't an issue - AL takes "TOP" talent from around the nation, they can't get everyone and can stop in-state talent from going elsewhere, even to a competitor. The fact that JMac is being successful I would think does two things for Saban. For one, he may have a bit of pride in that someone he helped along their career is being successful as it reflects well on what Saban has done in the past. More than that, I think Saban sees a new challenge on the horizon, a means of focusing his efforts and his program to not just maintain status quo but to adjust to the new dynamic in order to stay on top. I think he likes it. Until now, he's been watching Les eat grass, Hugh gather talent but under perform, Dan have a string of good luck that can push Saban but not really challenge him. Basically everyone in the SECWest has been good, but not (consistently) great so while it has been a tough job to win it regularly, it hasn't truly challenged him - certainly not in any new way. As for the SECEast, it's been more of a cupcake schedule for him the past few years. Now, finally, he might actually have someone that can push him.
I don't think he's worn out. I think he's tired of succeeding with the best competition he could find and is excited to have a new challenge.