It seems to me that you're mostly talking about RPGs. I can't think of any NES-PS1 platforming/shooter/action games that had 60 hours worth of content.

If you look at today's RPGs, they're still _really long_. It is expected that most players who play Persona 5 Royal will take over 100 hours to complete it, which is pretty wild considering it's not a 'grinding game'--players aren't taking that long because they're fighting the same enemies repeatedly hoping for a rare item to appear. There really is 100 hours' worth of contents.