It falls in line with other speculation like, exchanging closing during a sell to prevent a full sell-out (gox did it twice) and coinbase has a way of it's own.

But the problem with this one is volume.Yeah there are 200k unconfirmed transactions but
-how much is spam
-how much is close to dust level
-how much is just people moving around coins

To really make a dent in the markets you would need volume. And guys who can't afford 15$ per tx would not be able to do it.

Of course you could be one of those guys , transferring 2 million$ with a 3$ fee and waiting for two days already....
https://blockchair.com/bitcoin/transaction/605e6226505685cbbba1389dddae00716958f0410b5e6dc5970bef7be2fbc653