I find the inability to "connect" with older entertainment hard to understand, and a bit disturbing. Since I was in grade school, I was drawn to old movies and movie serials, old TV shows, old books and comics, even old music. To this day, I spend a lot of time reading stories from the 19th and early 20th century and older, and watching movies and shows from the 30s, 40s and 50s. And it seems to me there was a strong interest in the history of the arts in those days, at least among genre fans. We felt connection to the old and classic stuff through the evolution of the art form.
That seems to be sadly missing for most of the current generation. You see it in the complaints about special effects and the willingness (and eagerness) to colorize old films and upgrade SFX (like they've actually done with TOS), and in the constant characterization of old stories as "cheesy" (when, in many cases, the writing is indeed more sophisticated than in contemporary entertainment).
One of the things that always drew me to the creative genres was the variety of styles and approaches to be found. Retro fashion just adds to that variety (if you were to read my books, you'd find sprinkled in there various homages to Shakespeare, Bradbury, Clarke, Lord Dunsany, Donovan, Poe, Frost and American Indian folklore, among other things). These days, not only is there a generic sameness about (most) everything, but there seems to be a strong disdain of the variety to be found in history, and that's a terrible shame.
I think the frame of reference has changed. I grew up in the 70s and most of what I watched in reruns and so on was culled mostly from the 50s to 70s, occasionally dipping into the 40s or 30s. Extrapolating, that means a kid today is going to see programming from the 90s or later, occasionnally dipping into the 80s or 70s. Earlier stuff is going to be from the stone age.
And with all that material produced today plus DVD/Netflix and video games, internet, etc. they might not even need to go back that far. It's probably harder to appreciate black and white stuff when there's maybe four channels on TV to even see it.