eustachian≠fallopian, I like your observations about things becoming popular here at SDMB. I had considered a new thread on the associated topic of how peer pressure might assist in forming one’s tastes. I believe this notion might be among the factors underlying the OP’s concerns.
I realize the basic question is whether someone/anyone has studied how/why things become popular, and I suspect the answer must be a timid “yes” until someone can produce a clear example of such a study. I think the ongoing debate about what form that “study” must take to be allowed as “official” is of value. But I would hope the underlying issue in the OP is more along the lines of what the outcome of that study would be.
Since this isn’t a new topic for my own thoughts, and is something I wonder about often, especially when fads and “in” notions are so against my own preferences and tastes, I’m more curious about what the answers are than whether whoever found them was qualified to do so.
I had a basic Sociology course and a few follow-on courses back in the 60’s and I must agree that the “science” is soft and hardly more than economics or political science. Nevertheless, there are serious people, accredited by universites, who do think what they’re doing is legitimate science. I suspect there are some astrologers who have similar convictions. But I’m less interested in whether Sociology is a viable “science” than in some of the “theories” that sociologists may produce.
As far as that goes, I’m rarely convinced that the “findings” of archaeologists and anthropologists are any more ironclad than those of psychology and sociology and the other -ologies others take seriously.
The probability that some hypothesis (such as those already mentioned in this thread) might bear on the truth behind the OP’s question, would satisfy my own curiosity for what it’s worth. I’m not trying to speak for the OP.
FWIW, I do believe that it’s something more than random chance and the alignment of planets that underlies why some things become popular and “in” just as there are similar reasons why things go “out” and become passe’.