What does implementation details have to do with expectations? You can't just say the general public's expectations don't matter because they don't understand the implications of network routing.
Do Tor users expect their communications to be private? I think the answer is obviously yes.
Then why bother setting up any encryption at all? Why not just call the Internet an "anonymous network" and be done with it?
It's clear there is some difference between "expectation" and "informed expectation." If there were no distinction, then claiming you expected privacy in any situation would be legally sufficient to eliminate evidence collected while "violating" your expectation.
Because the law's notion of expectation of privacy is based off of the concrete reality of the tool, not of the abstract wish.
If you're a well informed Tor user, you would not expect coverage from the classes of attacks described. The Tor project itself specifically said that Tor does not defend against things like state actors.
Do Tor users expect their communications to be private? I think the answer is obviously yes.