Jon Stewart ironically fits that bill:-). Which brings up one reason why that tends not to happen: most people upon any brush with politics immediately want to get as far away from it as is humanly possible. Just running into Ted Cruz in the hallway may all be itself trigger that kind of flight response:-P.

So what “needs” to happen is not the same as what “will” happen. Always remember the implied second half of that type of sentence: “in order to survive, <this> needs to happen”. But not everyone gets what they need to survive, and the same holds true for nations.

Though the above two paragraphs may seem unlikely to be able to reconcile with what you said, there are ways - like a local project could be done by an NGO or even a non-/not-for-profit corporation, bypassing government entirely. Unfortunately, that power can be used to evil ends as well too:-(. But when it works - like Jon Stewart, and John Oliver - it can be extremely powerful!:-D