So I sit on a lot of PhD thesis committees, and have been to scores of PhD defenses. However, I have never been on a social science PhD thesis committee, and therefore have not been in the room for discussions about the "value of [the] research to the corpus of human knowledge." Basically, I don't know enough about the field to know what constitutes a valuable contribution.
And neither do you. What you have done here is no better than the idiot congresscritters that publish their annual "can you believe these projects are getting funded by the National Science Foundation! Chirp. Chirp." Because, when I see those lists, in the fields I know about, my answer is always, yeah, that makes sense, I can believe they have been funded.
And this situation is even worse, because there is no indication that there were any resources "wasted," so you don't even have that.
In the end, ultimately the objective of a PhD education is to increase the knowledge of the world. If, by using some aspect of the works of Taylor Swift, the student has been able to increase our knowledge about and understanding of the world, then they have accomplished the goal of a PhD. What value that contribution has to the world we can argue, but what contribution it has to the field in which the person works, that's going to take more expertise and knowledge about the field than I have. As such, I have to rely on my colleagues who do work within the field to make the assessment of whether the contribution is significant, and my ignorant opinions really don't matter.
Again, we aren't talking about how to best use public funding for research, we are talking about educational standards of an institution and a field of study. Saying, "it was based on Taylor Swift" is a lame attempt at, what, poisoning the well? At best. Temple University gave Bill Cosby a Ed.D. (Doctor of Education) for his thesis on the educational role of the Fat Albert cartoons. Yeah, because what he did made a contribution to the knowledge about education.
Do you have any legitimate complaints about the thesis in question as to why the work was not appropriate for a PhD? Have you read the thesis? Or an abstract? Or is this merely a dismissal of the value of any social science research?
PS Sorry for the rant, but damn this pisses me off