It was in the '70s that knee pads and helmets came to be ubiquitous!
When I was growing up, there were NO such things at all and we played on playgrounds, that didn't have rubber padding under foot, played on monkeybars, swung, seesawed, and rode our bikes, IN THE STREET, sans padding, helmets, etc.; even rollerskated in the street! And I'm talking about doing all that in NYC! :-)
No seatbelts, almost ALL adults smoked, yet children could see movies and T.V., listen to the radio, without being inundated with F bombs, nudity, and worse.