I think he really wanted to clean his image after leaving CLE the first time, and probably his ego led him to believe he can win wherever he goes.
100% this. You said the exact words I was thinking in my head.
If he truly wants to admit a mistake, he should apologize for leaving Cleveland the first time (and especially HOW he left).
Of course he never will, because he tries to act like Paul/Ray/KG coming together at the end of their careers via trade, some how justifies him, Wade, and Bosh orchestrating their own come-together in their primes (LeBron/Wade were the 1st and 2nd best players in the league, while KG was top 5ish and Pierce was top 15 probably).
The media/fans probably helped inflate his ego as well, because he got most of the glory and Wade/Bosh don't receive anywhere near the credit they deserve for making those teams that good.
If he never left Cleveland and somehow managed to pull off some championships there (or teamed up with vets later on in his career like KG and won a couple later on) then perhaps he could have gone down in history as a top 5 player.
As of now, however, there's no chance he belongs near the same level as guys like Larry, Magic, and Oscar, especially given the way the refs baby him. I'm not even sure how he'd match up with guys like Dr. J, Havlicek, Jerry West, Baylor, etc. if they played in the same era. I know if LeBron played in the older, more physical, era, he would be a completely different player.