Shaq won his last title at an older age than Kobe though? His decline just happened sooner than Kobe because he was way older than Kobe to begin with.
Although Wade did most of that lifting for his last title so shrug.
Shaq got back in shape just to stick it to the Lakers and Jerry Buss after being traded. No telling if that happens if he stays in LA, even with Kobe. Injuiries and playing himself into shape (probably linked) were an issue his last couple of years as a Laker. Also the other reason the Lakers wanted to move on from Shaq that nobody talks about (understanably, its not as juicy as the Kobe drama) was that as these (specially Shaq) guys age, and the nature of their contracts (again specifically Shaq who signed a pre-salary cap deal and was commanding huge money) it was going to become increasingly tougher to build a team around them. Depth is what really killed these teams in 2003 as the role players (Fox, Horry, Shaw) started aging and the best they could do to replace them due to the salary cap was old ass mother fuckers on vet deals (Malone and GP).