This doesn't make any sense at all. Standard heat pump installations include a buffer tank (usually at least a couple 100 liters but possibly much more dependin

This doesn't make any sense at all. Standard heat pump installations include a buffer tank (usually at least a couple 100 liters but possibly much more depending on the details of the installation). The heat pump does not heat the house directly, but the buffer tank. The buffer tank in turn sends warm water to the radiators and warm water faucets, etc. This is the same principle as in traditional gas and oil boilers. The only difference is that in newer, well insulated buildings, radiators need much lower temperatures so they may feel colder to the touch (i.e. you don't burn yourself on a radiator anymore). But modern heat pumps also can provide relatively high temperatures in case of installation in older buildings with legacy radiators (70°C are not really an issue anymore). "So heat pumps exist but just as a "not very good" alternative, relegated for things like small secondary homes at the beach (where it doesn't get too cold anyway)." In Germany, famously not a very warm country, heat pumps are used in well over 50% of all building projects requiring a permit (this includes renovations). Heat pumps are the definite standard, not an "alternative".