I think you're talking about the Mahayana bodhisattva ideal. Someone who's on the cusp of being enlightened might harbor egoistic motives, so that would indeed explain the desire to help others. But the end goal would still be nihilistic and would entail amorality, making nonsense of the bodhisattva's selflessness. Unenlightened folks want to help each other, out of ego and ignorance, according to the Buddhist picture. The goal of enlightenment is paradoxical in that this state beyond ego must be beyond society too, which puts it beyond morality and thus beyond the call for compassion, joy, etc.

The absolute counterculture this hints at is a transhuman one, I think. The nonpoliticized arhat would be a transhuman, a being as alien to an average moral human as the latter is to an ant.

But I should write something to apply this nihilistic view of "enlightenment" to the bodhisattva narrative.