I guess it depends on the individuals as I got my Genesis when I was 4 and I kept everything in excellent condition, including the boxes and manuals. I always tried to take care of my stuff, sometimes some things I owned like comic books got accidentally damaged but it's not like I wasn't bothered by it.
Another part is that things are just more fragile than they used to be. Compare cartridge games to disc games, and cheaper cases compared to PS1 cases. I don't think you can snap a disc when removing it from a PS1 case if you tried. Some DVD cases are difficult to remove discs from, earlier ones were better quality. Or just compare letting kids use VHS tapes before DVDs came along, or cassette tapes before CDs, or a Gameboy cartridge compared to a DS cartridge. Or the original Gameboy to the GBA SP with it's breakable hinge. All these things aren't designed to be as durable as their predecessors, almost on purpose so they're more disposable.