A benevolent dictatorship cannot exist et alia because a person cannot live for ever and I simply don't know how you could assure that the transition from one benevolent dictator to another when the first one ceases to be competent. For instance, let's presume that Xi Jinping is the perfect president of China. When he dies or retires or becomes too ill to govern, will the PRC be able to select a new perfect president to replace him? or will they choose someone who is inclined to serve their own interests and was able to benefit from Xi's time? This is the ultimate problem of a benevolent dictorship: it cannot assure state continuity and stability beyond the effective lifespan of the dictatorship.
People also tend to become more habitual as they do something for a long time. Politeness and friendships limit them from being able to introduce policies that will benefit the country at the expense of those who have their ears. So it's possible that a governing style which served the state and the country well for many years will need hard revisions. Periodic changes in governor (as democracies have) mean it's more likely the incoming team will be able to retain what is still fresh and discard what is now stale, and they will be connected with different people and therefore not too worried about upsetting some of them. (I think this is a good part of what's wrong at the moment: major parties around the world are connected too much to the same interests, so a change of government doesn't result in as much upset as needs to happen. Votes will gradually transfer from the establishment to the anti-establishment parties. They will be able to upset the entrenchment, but it remains to be seen whether they will do so in the interests of the nation or the interests of an alternative elite.)
As for your last sentence, I think I misunderstand it. I disagreed with you and straightforwardly stated my opinion, and then it seems that you attacked me: it reads like you're accusing me of not being able to handle disagreement. I don't think I attacked you. Perhaps you would clarify it, or highlight the place where you think I "don't take too kindly to disagreement".
