Even determining wheter a left feedback is "legit" or not (and should hence be removed) is going to far. The feedback system is yours to use, and it is to be used at your own discretion.
I also think we're too easy on the definition of "abuse" here. The system was designed so that users can leave their feedbacks, can leave them freely, up to their own decisions.
That's how it is intended to be, you're supposed to leave your trust feedbacks, it was build for it, and hence doing so can't be an "abuse" of the system.
As you have said there were also exceptions and that is what i am trying to emphasize as well, just like what happen to yahoo recently https://bitcointalksearch.org/topic/tbearhere-community-reaction-1722426 iF that was being moderated before the tagging happens there could be a better review first of what really happens.
Being Free anyway is the best thing that i human being should have. Yet limitations were also been a part of it.