30 year old's back in time looked like 70 year old's because they have lived 70 years our time.

Or....life was much harder at that time. They grew their own food, built their own homes, raised their own meat, and medical and dental care was scarce.

Think about what you are saying. Right now we strive to eat as healthy by growing our own unprocessed foods and raising our own hormone free meats.
Most people can agree that 1 hour when they were a kid felt a lot longer than it does as an adult. If we remove what everyone has told us what conclusion would you come up with going by just your personal experience?

I think time moved slower when we were young because we weren’t tied to it. No watch or cell phone meant we had the freedom to live in the moment. Most adults are chained to the clock. The day starts with turning the alarm clock off and the day ends with setting it to go off the next morning.