It’s often a very powerful form of nostalgia because all you have to go on is the romanticised, filtered version. The mod/northern soul scene is something to behold. I’ve been in people’s houses that looked like museums. They live and breathe it despite being born in the late '70s / early '80s.
For me there’s a fine line between knowing appropriation / reference to a past sound, when you understand and play with the context, and just slavish devotion to something you’ve decided is cool. Certain bands like Broadcast and Belbury Poly manage(d) the former, IMVHO.