The OP holds much wisdom.
I'm seeing more & more bike boom ten speeds being ridden by kids a decade or so younger than the bike. Seeing a cute junior college girl perched on a Varsity or Peugeot is a blast from my past.
One of the nicest riding bikes I ever had was a Viscount Sebring picked up from some guys lawn for nothing. "Free to good home"? That's me! Steel wheels and stem shifters- no problem. Sold it to a kid starting his senior year of high school.
Don't obsess overly with equipment. Ride the damn bike. If I'd have learned that one years ago, I'd have saved a lot of money and heartbreak.