United Kingdom

Correct me if I’m wrong, but surely both are necessary parts of the solution given the trajectory we’re on?

Absolutely, but critically these don't address heat. More importantly, swapping a gas boiler for a heat pump in a poorly insulated home will just result in wasted energy and cold/damp people.

In order to counter that we need an efficient way of moving heat from inside back out again without letting any more in, which is not something many houses in the UK can do today.

In 2025, most people in developed hot countries are using air conditioning in addition to everything else

While I can't speak for the whole of warm countries, my wife's family is Greek and we visit often, where air conditioning is surprisingly limited given the temperatures they endure. Instead you see shutters on windows, tile floors (with rugs they pull out for the winter), and tree cover that shields the home from the outside. That's not to say that AC isn't common, it is, and rolling out solar everywhere is a great way to deal with that. My only objection is to the common refrain of "more heat pumps" without acknowledging that most homes in this country are so poorly insulated that any temperature regulation is lost unless it's constant.