Fair enough, but the risk could also be mitigated by relocating the author/curator/commentor rewards to interest rewards. Currently, author/curator rewards takes up about 72% of the inflation with staked interest at 16.8% and witnesses at 11.2% of the inflation pool.
By cutting the author/curator inflation in half, you could have 35% of it remaining and relocated mostly to interest. If 10% went to witnesses and 25% went to staked interest with 37% eliminated, you could keep staked voters in control while making the witness role more lucrative and thus more secure and competitive.
That would mean interest would receive 41.8% of current inflation while witnesses receive 21.2% of current inflation and a cut in total inflation of 37%. Staking for interest, SP and RC delegations could prove more lucrative for stakers, potentially resulting in an increased demand for the supply.
Reducing or eliminating the posting rewards in favor of staking for interest or RC delegations is not out of the question. However, let's suppose that one or several SMTs are succesful.Wouldn't it prove to be more logical to port that model to steem instead of eliminating the rewards pool? We may need to eliminate the ditribution of steem to content creators sometime in the future but I don't see that happening unless we have something to take it's place.
I don't think it would be for the best. I believe many of us are beginning to see that the POB system is best made for small communities and not as an all-purpose voting system. As a previous Steemit blog article brought up, it is not fair to subject art communities to the stake-weighted voting of a whale that does not appreciate art, while an all-purpose stake-weighted system does this.
Let me put it another way, frequently the people interested in something like a stake-weighted curation system leveraging crypto would be crypto investors. In the case of Bitcoin fans, a very large amount of these members are red meat eating capitalists that might not value vegan recipes. In this case, it would be better if we could separate the vegan fans from the steak-loving capitalists that are only interested in curating moonboy predictions. So, the main solution to this problem is to allow for many smaller, sovereign POB systems.
As far as managing different groups of people this can be addressed with the implementation of communities using hivemind but you are probably right if we consider that value distribution using a single token can be problematic if one community has way more stake than another one. I still think that we need another vehicle to distribute steem to as many hands as possible other than just with block rewards and "interest". Maybe we can reduce the rewards pool to a minimum and just allocated to steem related content.