There is an ungodly huge difference in what city life was like 100 years ago to now when GM and auto manufacturers destroyed public transit. I've spent years going over the history of it and have used that knowledge in firms I've worked at. I don't have time to break it down in detail, but here is the general main events that happened in the last 100 years:
Auto companies (AC) bought public transit and immediately tore up the tracks/infrastructure
AC's lobbied hard to blacklist public transit
AC's aggressively advertised cars as the freedom of mobility
After WWII AC's used GI bill and auto friendly presidents to destroy black neighborhoods and establish the future as car
AC's sabotaged the development of Amtrak and other public rail projects
City/state zoning was incredibly incompetent putting R1 single family homes at the edge of cities
Local and federal lobbying efforts from gas/oil companies ruined any plan to reintroduce public transit
various gas, auto, and roadway ceo's/presidents became secretaries within the highest levels of the US government.
There is an insane amount of info to unpack and those only barely scratch the surface. Those are some of the main events and actions that have ruined our kids ability to navigate independently and do so safely. If you're interested in learning more, check out videos from Not Just Bikes (YouTube channel) and the subs r/fuckcars and r/Suburbanhell