I think the bigger problem, as others mentioned, is shadow interests buying/selling to create speculative bubbles and subsequent crashes. They could orchestrate these events at critical times (during a version release or media event) to discourage new users. Shadow interests will have enormous funds and won’t be concerned with making a profit.
Even if they could corner the market, it wouldn’t do them any good. The same goes for buying and destroying. Both would cause massive deflation and an ever higher price.