I think that can make this bitcoin price stable when there are no more enthusiasts, which means no one will buy bitcoin anymore, the price of bitcoin will be stable because there is no demand anymore.
Bitcoin having stable price can stop traders because they cannot gain profit for short time which is impossible to happen. Bitcoin price always fluctuates because of the demand of it. Having stable price makes it for more holding of the coin which can change the price when the supply become more limited. I think it hard to achieve stable price of it
There is nothing to be done to make the price stable because it is the characteristic of bitcoin to be volatile which make us get profit even in trading. See what is going to happen when everyone keeps holding, the price goes up and when many are selling the price gets down. There is no stable value because it depends on the demand and supply of bitcoin.