Comment by agentcoops

Yeah, I've lived in London, New York and San Francisco for work and the first had the lowest cost of living in absolute terms. Local developer salaries are, however, shockingly low outside of finance and consulting to US eyes.

The public transportation point is definitely key: London is just so unspeakably large spatially and it's all more or less well-connected that there isn't the same scarcity of commutable apartments as in NYC/SF. It wasn't uncommon for older colleagues to even commute in from Kent or elsewhere in the English countryside -- and often their morning train wasn't much longer than my own.