Of course, it's not "just about the cost". However, you could say it is "mostly" about cost of living and standard of living.
It's cool if you think suburban living is evil, but don't just say it is evil. Instead work to create a better city with better schools and lower crime. Basically what I'm saying is:
Stop whining and do something.
I could not say that it is "mostly" about cost of living (edit: or standard of living, which is subjective).
Who's whining here except you about how the suburbs get a bad rap for being evil? Why don't YOU work to make YOUR urban center better, fix the schools, stop crime, and stop hiding from the big, bad city in the sprawl and disposable lifestyle of the cushy suburbs?