~13% of the UK population, and growing, lives in London. Why would an unaffordable place be home to such a large portion of the population? It wouldn't. These cities become large — and continue to grow — because they are most affordable in the typical case.

Small towns often have a lower sticker price, but the low sticker price is low for reason: Because it is much less affordable. Everyone would be moving there if it were more affordable. Humans love to chase a good deal. After all, even London itself was just a small town, even rural, at one time, but people moved there because it was a better deal and thus the city you know today was born.

Of course, there are always outliers. Perhaps you are one of them. The earlier comment was clear about 'generally'.