The truth is that fixing these problems is going to be expensive. Governments are just kicking the can down the road because they don't want to be the ones that raise taxes to pay for it (fixing existing houses I mean). But it will have to be done.
Maybe the biggest tragedy is that we are still building NEW houses that will have to be fixed in the future (except in the above countries and some others I no doubt missed). Not mandating higher standards is, however, just loading future generations with more debt, because they will be the ones that have to fix the quality of the housing stock.
(FWIW, Sweden's neighbours like Norway, Finland and Denmark also have houses where it's warm inside in the winter without horrific leaks. And yes, Iceland, even if it has practically free, abundant geothermic heating energy.)
(But what horrifies me in England is not the wind through walls and puny glazing, it's the carpets in bathrooms, including around toilet seat. Experiences are not recent, though, so perhaps they've changed?)
I was referring to retrofit, sorry for not being clear.
Also, the costs are not passed on to customers. Very few houses in the history of the world have been priced according to what it cost to build. The market sets the price.
Carpets in bathrooms is a kind of baby boomer 1970/80s thing I think - plenty of it still about. Check the corners of the room where condensation pours down the wall into the carpet... after a few years you get a nice dark grey brown mould line.
But still, it's not the government that carries this cost.
Retrofit cost goes to government if the government decides to subsidize it. I live in Finland, which is considerably colder than Britain, not to mention Australia, and here the requirement for insulation is simply mandatory in building permits (which is required also for major renovation, not just new houses).
There are no real subsidies for this. Also, there are no heating grants which I hear are a thing in the UK (and a thing big enough to have an impact on how people vote).
Whether insulation is actually installed? Who cares about that - quarterly dividend payments all round.
Normally, doing that would be additional work and additional cost, so if they do it, there must be a real reason.
There's a lot of folksy wisdom in the UK building trade about natural ventilation (which isn't really true). Many builders will deliberately expose small gaps because they have not been properly educated. Having gaps gives poor ventilation - it becomes dependent on ambient pressure differentials which are difficult to control.
All of these are excuses for poor design and workmanship in the first place.
This might seem like more work for minimum wage labourers on site, but it's less work for highly paid designers, so it costs less. But costing is a difficult thing to sum because it's a complex supply chain with opportunities for efficiency all over. It's just that the volume builders (in particular) have a conservative interest in keeping the status quo, and carrying on without rocking the boat.
> Newer housing surely has better insulation
You only really know if you test and measure.
On the other hand I can run a homelab at home and don't feel bad about wasting electricity - I need to heat my apartment, anyway.
Say what now? Is the UK the only western country you've visited? because what they describe for Australia is not the rule of mainland western europe, serious insulation and at least double paned windows was the standard in the 90s.
And all that doesn't help with ventilation and maintaining healthy levels of fresh air.