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I don’t think there are intrinsic issues with them, just cost:benefit being misunderstood/missold to people.
They aren’t as energy efficient as people hope they will be, and for lots of people they want to do something more environmentally conscious, but price / money saving is a big factor.
Your top 5 countries will have different housing stock and energy prices which will affect the cost:benefit analysis for consumers there.
the popularity of ASHP in more extreme climates than ours suggests there are no intrinsic issues with them