I totally understand your frustration and that looks matter even if just subconsciously to everyone is quite the shitty paradigm to navigate. Humans being mimetic creatures results in all sorts of weird unfairness and idiocy.

However when it comes to advice, are we interviewing for a job in an imaginary world, or the real one?

If it's the real world, this is great advice. Just like having a marketing team instead of thinking every product will sell itself is great advice that almost every company in existence learns at some point or another.