Given that at some point, Satoshi Nakamoto decides to flood the market with his Bitcoins, he could very well tank the price of Bitcoin.
I don't see why he would do that however, no reason for him to kill his own baby.

My theory is more, that he simply has removed any access to his wallet, to prevent him from any temptations to cash it out in the future. Because today, there are quite some reasons, why he would like to crash the price (which would hurt the price of BTC - but not the technology or the principle behind it).
Because right now, the heavy speculation (and most likely manipulation, if we consider Tether and Bitfinex) on BTC itself is preventing BTC from being what Satoshi had in mind for it in the first place - being a currency.

This might be an romantic thought, but this is what I would have done back then.