People do not like to be uncomfortable. Nor do they like to be wrong. Should someone become "self-actualized" be it through philosophy or perhaps by being a monk, it is through much effort and discomfort. It is not easy to go from being a watcher of shadows to one who has a greater understanding of "life, the universe and everything".
Once one has become enlightened through personal sacrifice and they try to tell another that their ideas, way of thinking, and so on are wrong-no one wants to hear that. It is very uncomfortable and will be met with resistance. Tell someone that we could all live in a better society if they stop watching prime time sitcoms and sports and then spend that time doing community service or just checking on an elderly neighbor and likely they will tell you to pack sand. Or, substitute anything behavior or activity that they could do to better themselves instead of wasting their life away.
I think that the ideal state that he was proposing is like what our founding fathers had in mind with the "citizen statesman", rather than the career politicians that we have today. There is a warning that we should be wary of those who wish to rule. They most likely are not wanting rulership because they are going to make great personal sacrifice for the greater good and to make society better for all. One should be selected because they do not want the job, it sucks to be in charge. It requires much effort to rule justly, compassionately and for the benefit of everyone else, even at one's own expense. The ideal leader in this society would have to be dragged into office kicking and screaming, "No. not me!". However, once resigned to their task, they will give it their all until the lousy job of being the ruler has run its due time. Drag the next one into office, your time has been served.
Both Plato and our founding fathers expected that the society would be, by and large, well read, somewhat educated people, compassionate and caring, honest and just. Well, sounds good on paper...