Note that in moderate/colder countries (taking the Netherlands as an example), heat pumps are not a solution when your house is not up to modern insulation standards. Which is true for almost all houses older than say 15-20 years.
The insulation needs to happen first for those houses, and this can be a massive undertaking costing tens of thousands of euros. The next best thing is a hybrid heat pump.
Although there's some subsidies here and there, you're very much right that we need something way more aggressive. For the houses I mentioned (which is almost all), a total sum of ~50K EUR is just not something the average family can afford. Those that do probably up their mortgage to finance it.
Also take into account the shortages. I have a family member that installs heat pumps, he orders them by the dozens. Currently he's afraid to place orders as the delivery time is a minimum of 6 months with no guaranteed final date nor is the price fixed. It's "6K but we will charge you whatever it will actually be when we deliver". "I don't know when it is coming or what it will cost" is not a great message towards home owners.
