Is there a chinese musuem that just has Charlemagne, King Henry, King Richard, and Prince Charles just under one name?
Well that's not what's happening here, she specifically refers to Guanyin as an example if one figure with many names, but if a gross simplification like that is believed necessary to effectively convey the information they are trying to teach, then yes. Labels are an exercise in difficult compromise that even in the best cases are woefully simplistic.
A better example would be a comparison between the God of Christianity and the god (Allah) of Islam. We know that they are one and the same and that it would be disrespectful to a certain degree to both call them simply "God", but it may not be possible to explain the different names or calling him the Abrahmaic God may be too academic for the museum's audience. So referring to them "both", both being the related but distinct religious understandings of the shared god as God and Allah respectively, as simply "God" may make the text more effective in what it is trying to explain. That is why referring to Guanyin/Kannon/Kwannon as a goddess of compassion may be more effective as a tool for teaching guests than calling them by their "most correct" language/culture specific names, despite how much significant detail has to be discarded in the process.
