In London, where housing delivery has long trailed short of need, the population rose by 3.4 for every new home.
This mismatch of housing supply and need has had drastic consequences for affordability. Rents increased 2.0 per cent per year in England on average over the last decade, according to data from Hometrack. Growth ranged from 2.4 per cent per year in London, where housing delivery was lowest relative to population growth. In the North East, by contrast, housebuilding all but kept pace with population growth and rents grew just 0.7 per cent per year.
https://www.savills.co.uk/blog/article/309803/residential-pr...
The ratio of house prices to earnings, another basic measure of housing affordability, increased from 6.9 in 2010 to 7.8 in 2019 across England. In the North East, where we delivered almost as many homes as people, homes became more affordable. In London, where housing supply falls far short of need, the ratio of house prices to earnings has ballooned.
When you think about it, even in areas like London the housing market is not liquid nor uniform enough for the offer vs demand model to apply. You don't rent/buy home like you buy strawberries.
In about 1 year there was no significant increase in demand and the supply stayed the same but everybody saw its rent increase.
Edit: Also we should not mix-things up, the housing market is very different in outliers like London compared to the more global market. Here we're in the context of those outliers (Paris, London, etc.)