Shall I recount the reasons to thee?
Let's start with him always getting the calls: All Stars in Basketball get the benefit of the doubt when it comes to calls thus plays go their way more often than not. As Lebron is the biggest superstar in the game, even more calls will go his way. Back years ago, Kobe would get all the calls as well. It's just how the NBA works.
Then on to his whining. Yes, he whines, but so does every other player. It like the calls is just a part of the sport. Players whine to the refs or fake contact to try and get calls. You see it with Lebron more often since he is as previously stated the biggest star in the sport. Pundits talk about him more than other players.
Finally, his being "overrated"... unlike the other two points which have a basis in reality but are just warped by your viewpoint-- hate--, there is no basis in reality with Lebron being overrated. It is hard to overrate the second best player to ever play the sport unless someone was to call him the best. Almost every metric/ analytic supports Lebron ending his career as the second best basketball player ever.