You cannot expect people to act against their own financial interests and be altruistic, it's an unrealistic expectation.
Is it really altruistic to do something in the hope of a raising STEEM value?
I would accept not to earn one single more STEEM in case this guaranteed a significantly higher STEEM price.
In other words: I would accept to get a smaller piece of the cake, if that made the cake grow a lot. :)