Is it? Robust transit systems are efficient and don't take much more time. If it's substantially longer, maybe we need to look at our work attendance policies to account for the increased transit time? (We already needed to do that anyway, considering how little of the average workday is spent on actual work, and how much less the average labor hour is worth today compared to a few decades ago.) And how old are the kids? Alien as it is to suburbanites, city kids often get around by themselves (often in groups) by the end of elementary school.

True. And even with public transit, activities like taking kids to soccer practice / music school requires carrying some equipment along. Not really convenient lugging duffelbags if there is more than one kid.

The kids need to be picked up in a car partly (largely?) because there's no alternative. Given increased public transit, they may be able to get themselves to soccer practice.

Kids could walk, bike, or use the bus/train if the infrastructure was there.