Controlling an exit node alone doesn't help, but controlling both entry and exit nodes does. The tor project has network stats on their website: https://metric

Controlling an exit node alone doesn't help, but controlling both entry and exit nodes does. The tor project has network stats on their website: https://metrics.torproject.org/networksize.html https://metrics.torproject.org/networksize.html Looks like about 8,000 relays, inclusive of entry and exit nodes. Looks like about 2,500 exit nodes, and ~5,000 guard nodes. With that few I'd say it's reasonable to assume that a large number of both entry and exit are controlled by government agencies, at least enough to reliable to conduct timing attacks against a specific target they are interested in.