Really? That is very different from my experience.
If you're talking about the actual City of London then maybe, but most other places I have found quite lively and active in the evenings, especially around where I live.
If you're talking about the actual City of London then maybe, but most other places I have found quite lively and active in the evenings, especially around where I live.
And yet if you search for it on the Internet Archive, look how many different people used to live there, and they're just the ones that got their address written down durably: https://archive.org/search?query=craven+Street&sin=TXT&sort=... There are 22,000 results!¹
From a quick scan, we have architects, doctors, people dying aged 74, births, remarriage of a widow of a naval captain, soap-boiler, a tailor, a church donors, lords, ladies, "misses" and esquires.
The same chart has the population as 1,911,728 in 2020, about 10% smaller than a century ago. It's now the capital of a country with only about 9 million people.
My main point though was that Vienna's population decreased greatly after its empire, and while increasing is still 10% smaller than a century ago.
London's population has different dynamics, and I can't pretend to have a good reason. I can observe that https://en.wikipedia.org/wiki/Demography_of_London shows a clear decline correlating with its shift away from being an imperial power, from ~8 million in 1951 to ~6.6M 1981.
To another comment, I'd expect the City of London (i.e. the financial district) to be pretty deserted at night as very few people actually live there.
The thing is, for hundreds of years, it was indeed residential. Those were houses, built to live in.