I can understand the impulse that would lead people affirmatively to separate themselves from "politics," because politics appears to many to be a realm of lies and corruption. Keeping oneself out of such a corrupt and discouraging place can be seen as something that is worth some energy to accomplish. I do agree with Zunger, now that I have been presented with this analysis; he is correct that there is a group (he seems to think it's even larger than the "uninvolved"), who are taking care to be sure that they are not enticed into participating in a part of life that they think of as despicable.
But what of that modifier "comfortable?" I guess that this modifier is to suggest that those actively fleeing from any political involvement are doing that so as to be or remain "comfortable," since politics is all about conflict and controversy, and both conflict and controversy do tend to "afflict the comfortable." If that quoted phrase doesn't ring a bell that means you may be unfamiliar with Mr. Dooley, who says that newspapers should "comfort the afflicted, and afflict the comfortable." The press is part of politics, and any genuine politics really has the same mission.
I am not certain how Zunger intends the word "comfortable" to be understood, in the political schema he suggests. I want to say, though, that anyone who is seeking "comfort" by making an active decision to separate himself or herself from politics, is pursuing a flawed strategy. We do, in fact, live in a "political world," created and sustained by our own actions, and to make that world "comfortable" to us, to make it fulfill our hopes and aspirations, active involvement is the only strategy that works.