The automobile's net effect on behaviours has (as others have noted) evolved over that period, as has its net effect on transportation and urbanisation patterns.
Up until the end of WWII, automobile ownership was relatively limited. It was just beginning to accelerate at the beginning of the war (in the US), but rationing and war-time defence manufacturing curbed that trend, and sustained rates of alternative transport, particularly rail.
Post-war, there was a mass-consumer blitz, much of it revolving around automobiles, and changes such as commuter suburbs (based around automobiles), superhighways, self-service grocery stores, shopping malls, and strip-mall based retail development began, all trends which evolved over the next 50+ years.
In the 1970s and 1980s, it was quite common for children to walk or ride bikes to school, or take a school bus (which involved walking several blocks to a nearby stop). Since the late 1990s, far more seem to be ferried in private cars, usually by parents, who spend a half-hour or more in pick-up lines. It's not uncommon for children walking along neighbourhood streets to be reported (and collected) by authorities by concern for their safety, and their parents subject to investigation or worse. Suburban, and even urban development patterns have been to ever-lower-density and far more bike- and pedstrian-unfriendly modes.
Recreational, occupational, educational, and other transport and activity patterns are largely away from self-powered movement (walking, cycling, etc.) and toward motorised options (sometimes including e-bikes, electric scooters, or equivalents, though most often automobiles).
Societal change and consequent impacts take time and have long lags.
