This is what's been tried from about 1960 to now. It turns out to not be anything near sustainable financially, because the low density development doesn't provide enough tax revenue to pay for maintenance on the infrastructure. Once an inner-ring suburb needs to raise taxes to replace its water pipes, it starts emptying out to newer suburbs farther out that don't have to support legacy infrastructure and things like pensions. If you look at closer-in suburbs built 30 years ago, you'll see abandoned former Walmarts and Pizza Huts that followed the growth outwards once their buildings were fully depreciated. Austin might be slightly different because it's changing to fit the mold of an expensive coastal city from the inside out, but the pattern holds in other areas that aren't as trendy right now.