Yes, many people on the business end of entertainment can be inept. Yes, artists can be dicked over, and when they have "a vision" as you put it that they do not want to compromise, problems arise. Morrissey is not unique in this regard. Where he differs is in the frequency of major fallout. I agree that Morrissey shouldn't shoulder all of the blame for every record deal and professional relationship gone sour, but if someone has a recurring problem for over 30 years and consistently blames other people for that problem when they themselves are the only constant, it starts to raise suspicions.
What I find curious, which goes hand in hand with the paradox pointed out by Anaesthesine, is that given the decline of the major label system, an artist like Morrissey, who frequently complains of being held back by the incompetence within said system, should be rejoicing with the knowledge that he now has the potential for more freedom, more control of his artistic vision than ever before via other avenues, and yet he refuses to move forward with releasing music without a label. There often comes a time when artists who have been burned too many times take the chance to move away from a major label, or labels altogether, when presented with that opportunity. Morrissey could do this with minimal risk, and yet elects to remain beholden to the people he repeatedly deems obstacles in his way when he doesn't need to be. This doesn't make much sense, but then, Morrissey is a man of contradictions.