You're right. However, in theory, the massive buy pressure of the company buying and powering up 33 million Steem should help with that.
But you've raised another issue in my head. We all HAVE to sell Steem eventually at some point. We're not going to HODL it to the grave I guess.
Selling per se is not a problem. The key is to have an equilibrium between the quantity of steem being sold and that being bought. Think of a bank: if everybody comes to ask for their money at the same time, the bank goes bankrupt. Steem is the same: if we all sell at the same time, the price plummets and confidence with it and selling begets selling and the whole "value convention" collapses.
So in a sense the key is "timing" - decreasing the "velocity" of STEEM (a term from monetary theory)