Note that in some places (the EU for instance) self-installation is illegal since you need an F-gas certified installer. Of course, this may result in higher emissions than letting people DIY it, since it discourages switching away from gas....

Not in a HCoL area, quite the opposite in fact. Rural Maine.

Heat pumps are still a luxury product here that you only see on new homes or well financed gut remodels, which I think is the problem. As market is largely price insensitive individuals here, there’s no downward pressure.