I wasn't going to jump into this thread, and I don't agree with all of the premise of the OP. I will agree that he did overcome a lot relative to many top champions in their sports, but there are other examples of those who overcame more adversity (in my opinion) to rise to the top.
With LeBron, he has faced some harsh criticism but also universal adulation. As hoops is a bigger sport than tennis (in the US, and worldwide) it may have dwarfed what Novak has received, both good and bad. I like Lebron, and he is in the GOAT conversation. He's a good guy, but he has brought some of the backlash he's received upon himself -- "we are witnesses"; "The Decision" "Not one, not two, etc." That doesn't make him a bad guy...I sense he's a good guy...but he has talked about himself as the 'GOAT" and amazing as he still is at his age (sound familiar/), to most, he doesn't have the charisma of a Jordan or a Kobe. Better than? I always thought he was better than (the late, great) Kobe and there's a case to be made v. Jordan, but still lean to Mike (and to Wilt).
Novak has brought some of the backlash upon himself, at least starting with the Covid era, but you can tell from many matches how the crowd went overboard for Fed (2015 USO and 2019 Wimby among the examples) but it's gone beyond crowd reaction to his coverage among some (not all) in the media. Per LeBron, he's had some who genuflect at his every move and then high-paid trolls like Skip Bayless who make a lot of $ from bashing him. Overall, I think he's been treated fairly.