I think it's completely understandable from Kyrie's point of view why he would want to leave, and there is fault on both sides. LeBron's dominance of the ball really renders all his teammates into catch-and-shooters. Kevin Love used to be a nightly 20-20 threat and a deadly first option, try making him the first option now. The thing with LeBron IMO is that he can make a lot of role players better because they honestly don't need to do much other than hit shots, but he has issues coexisting with other (let's say) All Star-calibre players if they aren't his besties.
Obviously there isn't a lot of data here to back up my statement, though, and this could all be my own confirmation bias, but hear me out. LeBron is so ball-dominant the team relies on him (and he likes it) to run everything offensively. It gets to the point where when he leaves the floor, the team has no idea what to run and it's almost like they forget how to play basketball. This then turns into LeBron having to play heavy minutes because the team can't score without him and it's just a vicious cycle at that. Look at Jae Crowder who came over from Boston in the Irving deal. He was so good just last season in the team ball Boston was playing. He was absolute garbage at Cleveland, and it reminded me of DeMarre Carroll being good at Atlanta with team ball then going to ISO-heavy Toronto and being trash. People love to bring up LeBron going to the Spurs, and honestly I don't see that working out unless LeBron learns to get everyone involved every trip down the floor rather than one teammate at a time to rack up assist numbers.
Back to Kyrie, I definitely don't blame him for wanting to leave. I'm pretty sure the Cavs were in talks to trade him for PG and Bledsoe before the draft, and he caught wind of that which is why he requested a trade mid-late July, convinced that LeBron orchestrated it, which actually goes to show how bad their relationship was. The two of them didn't even try to talk and sort out their differences.
In any case, he's an All Star who grew up idolising Kobe Bryant, the guy who gets chastised and criticised because he wasn't the top dog for his first three rings. So now when you have the best player in the world on your squad, you'll never be considered the top dog, and it doesn't help that you're a point guard whose ball-handling duties are being taken away. Of course it doesn't help Kyrie's case that he hadn't been able to lead his team to anything without LeBron, so I do think there's fault on both sides.
Sorry that this reply turned into scattered thoughts that are poorly stringed together. Hope it's not too painful to follow :S