That transaction is a little unsettling to say the least. If such an individual decides to exchange that amount of BTC for fiat the market will be temporarily distabilized. However, I am convinced the owner(s) is a hodler if not they would have cashed out long ago.
Does it specify if it was moved to an exchange? Just being moved could mean an OTC sale, transfer to more secure storage, etc. Hopefully they would keep that OTC if they do decide to cash it out that way it doesn't flash crash the market.