Here in the US heat pumps are unreasonably expensive too... We already have AC, it's the same damn thing but backwards! There was a government credit to lower the cost, but I'm guessing that mostly affected the sticker price (since it was X% of the cost up to some maximum I think) so the heat pump company can make more. Adoption is more challenging if a building has older central AC as well, since we use different refrigerants now (much better for environment), but they run at a different pressure, so you need to replace the coils and all refrigerant lines, which is expensive.