According to Roger Keil, a professor of environmental studies and research chair in global sub/urban studies at York University in Toronto, to become more sustainable, cities need to start doing something with the suburbs, rather than doing something about them.
A 2022 book chapter Keil co-authored about the idea of “retrofitting suburbia” notes that “while there may be much to criticize about the suburbs, criticism alone will not help create a more sustainable, vibrant and… resilient suburbia.”
https://www.sprawlcalgary.com/rethinking-the-suburbs