Yep, like ECHELON and friends are. The metadata recorded about your (all of our) traffic is probably enough to perform the timing attack.

Hey, if ECHELON snuck a listener into my house, where six devices hang out on a local router... Good for them, they're welcome to my TODO lists and vast collection of public-domain 1950s informational videos.

(I wouldn't recommend switching the option off for anything that could transit the Internet or be on a LAN with untrusted devices. I am one of those old sods who doesn't believe in the max-paranoia setting for things like "my own house," especially since if I dial that knob all the way up the point is moot; they've already compromised every individual device at the max-knob setting, so a timing attack on my SSH packet speed is a waste of effort).