Kanye is a garden variety manic-depressive. It has likely been exacerbated by stress and self-medicating with the wrong drugs, causing instability, paranoia and delusion. Bipolar disorder is genetic, it doesn't develop due to no one being able to say "no" to them.
What you are describing, however, is one way that Narcissistic Personality Disorder can develop. Successful individuals are more at risk of NPD. One of the biggest issues is that NPD patients usually don't suffer, so they rarely seek treatment, which can correct if not cure the disorder in under 2 years, rare among psychological disorders. But the symptoms of NPD not only include an exaggerated sense of self-importance, but also an inability or fear of criticism, and exceptionally strong denial. Narcissists don't listen to anyone, such as those that are trying to help them, yet they require constant admiration.
It is likely West has one of the more benign flavors of NPD, at least, I haven't heard he is violent nor of reports of him berating and belittling others (though I do not follow celebrities). I think his biggest problem is BPD and drug abuse (though the self-medication may be keeping him alive, it is far less than an ideal solution), but due to the combination with NPD and vast wealth, and probably being surrounded by those that will never deny him his insane impulses, he's probably not going to get help until he bottoms out in clinical major depression for months, if he survives it. BPD must be maintained, and if it isn't, inevitably the train leaves the rails.