It's an interesting observation. I'm part of a few UK and Canadian regional subreddits, and the topics of conversation are often very similar. House prices are too high, we need to build more, the government is favouring boomers, the economy is stagnating, we need more manufacturing and less real estate speculation etc. What's particularly interesting is that often in the UK ones people paint Canada as being far better. The Canadian ones seem to idolise the US.
It's clearly a global structural issue. Low interest rates are a pan-national commonality - and they can take a lot of blame for part of the situation we're in now. But they don't explain housing shortages.
Population growth probably plays a big part - housing is always going to be lagging population growth. The various stories I've seen about Japan - with low rents, falling house prices and large numbers of abandoned houses - seem to map with the falling Japanese population. "Things were better in the 70s/80s/90s" probably partly just means that the ratio of houses to people was better. The population of most major western cities was falling or flat through much of the 70s and 80s - leading to the situation where my parent's generation all seem to have snapped up large, well located houses for not very much money.
I'm fully supportive of the idea that, with all things equal, if we build more houses then supply and demand will drop prices. But if you allow unchecked population growth (which in the UK and Canada seems to be primarily caused by immigration) then the amount of building required is effectively infinite.
I've visited the Toronto area from the UK more or less every year since I was a child, and the overwhelming story is one of huge development. The change in the suburbs of Toronto over the past 30 years has been vast and unlike anything I've seen in the UK. Yet that clearly hasn't been enough to stop house prices going crazy as well. The net effect, though, is that there's miles and miles of sprawl and 6 lane streets dominated by cars. The answer definitely isn't to build more of that. The population of Canada has grown by 40% in the last 30 years.
Population growth combined with an ageing population and the kind of rights purchasing a house gives you in the west create increasing inequality driven by land. That seems to be the underlying issue that's driving city house values up everywhere.
There are possibly some answers. In the UK in the 60s-80s we built entire new cities, with the land purchased by the government at agricultural value so that the entire uplift was captured by the developers rather than speculators.