You never even seen the Netherlands, have you? Also, what I tell everyone who comes up with these kind of non-questions, no one is taking your car away. Cars still exist in Europe, but they are not the default, they are used for what they make sense, making irregular trips of 100+Km. But chances are, that there is a train that serves the route anyway.
Handicapped people: most have access to electric micro-mobility vehicles that are legal to use on bike lanes. For those who can't use micro vehicles, there's still cars, and vans. They still exists. They weren't magicked away.
Kids: My sister lives in the outskirts of Madrid, her neighborhood is littered with dozens of parks of all kinds, all less than 10 minute walks. My 10 y.o. nephew can go on his own to many parks without ever having to set foot on asphalt, cross a road or get on neither a bus or a car. He has never had to play on a street. They live in an urban tower that, while they don't have a personal green cancer backyard, they have a skatepark, a playground, a pet park, sport courts (tennis, badminton, soccer and basketball), a running trail and a botanical garden, all within walking distance.