I dunno, it seems like modern cars are heavier than old ones. At least similarly sized. I bet if you compared an old Dart or Valiant to a modern mid-size car, the modern one would be a couple hundred pounds heavier.
Yep, My Dart is 3250 LB,
mustang gt 3600 LB,
mustang gt 500 3900 LB,
new gto 3770 LB,
Dodge Charger 4200 LB,
Dodge Chalinger 4100 LB.
Corrvet 3300 LB.