That's very easy if you don't have kids - just don't get on a hedonic threadmill (and, if you're already on it, start gradually getting off). I'm not a parent myself, so won't speak about the "with kids" situation.
The average Londoner is paying almost 40% of their take home pay on rent, so saving 2/3rds is already impossible.
Even as one of the lucky ones earning a top 1% salary, I _still_ pay 40% of my take home pay on a mortgage with a 33 year mortgage term!
Your idea of getting off the treadmill must be living in the countryside and taking a 80% pay cut, I suppose?
Before coming to London I was doing an equally demanding role on 20% of my current pay.
Or how about raising a family in a 1 bedroom flat? - i see loads of people doing that these days. My old neighbours both had full time well paid jobs and were still in a 1 bed with a newborn.
There's no real escape. The economy is a dog, and we are all underpaid.
Now 9% of my takehome goes on rent, and I have no idea how I could ever go back to the UK. The energy bills alone are mind boggling, and every time I visit it just feels like it slips further and further behind the times.
The problem in the U.K and especially london is that demand for housing outstrips supply. This denies opportunities to most of the country as the only way for young green people to live in london is to live rent free with parents who paid two years worth of wages for a 3 bed semi 40 years ago, for a house now 10 times wage
The average ${global_alpha_city_dweller} is paying almost 40% of their take home pay on rent
There is nothing particular about London in this context. What about New York City or Sydney or Hongkong or Singapore? Pretty much the same. (Tokyo is an odd duck.)
Also, this:
Even as one of the lucky ones earning a top 1% salary, I _still_ pay 40% of my take home pay on a mortgage
I agree. Living in London is for people who don't mind to work till they're old. I lived there for nearly a year and concluded that, while it's obviously an awesome city, it's not worth spending an extra decade (or more) working just to pay off mortgage to live there. I chose to live in an less awesome city, and thus am already retired at 42 years old.