That may hold for a certain class of human situations. However, User:alexflint's story indicates that User:alexflint did endure a gross cost [1] greater than what would have resulted from not applying filters for popularity. The alternative to allowing one to be influenced in this matter is not to impose an impermeable "clean room", but to simply avoid avoidable expenditures when the source of the bias is noticed.
[1] though as I've made clear, not necessarily exceeding the benefits to terminal values
I just downloaded the latest Radiohead album, and I love it.
Thinking back, I started listening to Radiohead years ago when I found out that some of the cool kids in school were into it. With all the hype about the new album, the status/fashion processors in my brain going to ensure that I enjoy listening to it. I would probably fail a double-blind test with a bunch of imitation bands' fake "new Radiohead albums".
But I'm really enjoying listening to the album, and that doesn't seem like a bad or contradictory thing at all, even in light of the statements above. If, hypothetically, I was enjoying it for purely non-fashion reasons, then presumably that enjoyment could also be traced back though a causal chain to facts about brain development, evolutionary psychology, or whatever. But we would have no problem accepting that enjoyment as A Good Thing since explaining enjoyment does not diminish it. And so it seems in this case.