I'm sure we can find cities/new developments where gas lines were not run, but have we examples where existing infrastructure was finally shut down?
If you want to achieve carbon neutrality in 20 years it's ambitious and you need a plan. Phasing out the gas-infrastructure is one of them. And housing and its infrastructure is so permanent, our gas heating is as old than I am, at least it looks this way.
Nobody has explained to me sufficiently in plain language how carbon dioxide is bad for the environment. I've heard plenty of good explanations for water control, but my limited biology understanding has me presuming that more carbon emissions is advantageous to plants.
The IPCC reports have it all. Their models include plant growth already. Google it.