This is also a function of transit efficiency. It’s not the distance to a metro center that is the problem, it’s the time to get to that metro center.

Yeah, but the further a suburban neighborhood is from the metro center, the more time it will take to get there, necessarily. Maximally efficient transportation would minimize the travel time but not eliminate it. Even with great transportation options, the further the sprawl, the longer the commute.

Not even going to mention the poor design of suburban areas that lack a proper downtown of their own.

But if a suburban area grows enough to need urban infrastructure it kinda stops being suburban. Which is fine, there’s nothing wrong with increasing the number of urban areas. I don’t think we should have only a few Tokyo style mega cities. But I also don’t think higher density is necessarily a bad thing. I get that not everyone wants to live in a relatively high density urban area, but I’m also sure that we can’t just keep sprawling out forever.