When i was a kid a friend of my grand mother was arrested because a neighbor said he was a communist. He was tortured for a week and his party, kind of center/right wing took him out as they were a close party to the current government. Oppressive regimes usually don't need evidences.
A friend of mine was arrested for two years, accused for terrorism. The proofs? a war and peace copy (not even a photocopied book) and a guns and roses poster. And this was in "democracy"... so stupid proofs are also used, and whatever can be a proof, like a book about cubism was considered that was a book of cuba's ideology.
Tor has been for years looked by "regular"/"normal"/"common" people as a tool for drug dealers or child molesters. The switch to a human rights tool doesn't seem to really put it more into the illegal line.
Anyway, oppressive regimes do whatever they want, Tor can avoid some of the spying but if the state is already taking your computer you are screw up with Tor or without it.
And people on Pieter's side of this issue probably think it also logically follows to prevent that mental connection from happening in government officials' minds. Just gotta change how it's branded.
If it's as concepts, "human rights" triggers less alarms than anonymity, first because while I don't know which regimes you consider oppressive there is a big probability they themselves think they comply and/or promote human rights. Iran for example have a Islamic Human Rights Commission and proudly promote it. Israel would be another country that fits this example.
Then we have that anonymity could mean something it scares them the most, which is not human rights defenders but spying. Tor is already in a bad list for this reason, same as any anonymity software. The biggest threat those countries face is still military intervention or terrorism. A friend was arrested while taking pictures in Palestine, when questioned he was asked if he had Tor or i2p installed, PGP or any encryption software on his laptop. They didn't took his laptop away, but that was before the switch to "human rights" brand.
Then there is another vector we can take, Tor as circunvention. Another friend when visiting sudan got a pamflet to not use Tor, VPNs or Proxies when asked for the visa. The hotel made the same requeriment. This was 4 years ago. The reason was not that Sudan has been in the list of the worst human rights offenders but that you could access immoral content with it.
So, while I understand the point, it doesn't seem to have a backed reality to be sustained.