Either your example is too trivial to justify your point, or the point itself is trivial. It's right for an academic to distance themselves from the subject of their study because we do need researchers who try not to be biased. If they fail that and then correct themselves, then what's the problem? Complaining about inconsequential uses of tone is obsessing about form over function and reeks too much of insecurity, to be honest.
Of course language does not guarantee that the study is objective—that would be in the design of the experiment, the reproducibility of results, and the absence of conflicts of interest among the researchers. Using the passive voice however elevates the outcomes being reported as facts that actually happened, instead of mere personal experiences.
People complain all the time about news being biased for being told from a reporter’s point of view, but complain all the same when events are reported in an encyclopedic manner as researchers do when they remove themselves from the events and the outcomes of their studies.
