Yes, Berlin is the most obvious candidate at this point, and it seems strong on most fronts except climate and prices.

Prices aren't bad compared to other big cities.

You would need around 3,087.02€ (2,438.53£) in Berlin to maintain the same standard of life that you can have with 4,500.00£ in London

You would need around 3,073.39€ (2,427.76£) in Berlin to maintain the same standard of life that you can have with 3,600.00£ in Oxford

You would need around 3,084.93€ in Berlin to maintain the same standard of life that you can have with 3,400.00€ in Vienna

You would need around 3,093.66€ (3,484.64$) in Berlin to maintain the same standard of life that you can have with 6,000.00$ in Berkeley, CA

You would need around 3,077.66€ (3,342.51Fr.) in Berlin to maintain the same standard of life that you can have with 7,300.00Fr. in Zurich

It's not anymore the price level it had when Tim Ferriss wrote the 4HW and recommended digital nomads to move to Berlin to have it super cheap, but it's still relatively cheap.

Which city do you consider suitable that is cheaper than Berlin?

In most cities I think you couldn't run an event like the LWCW for 150€.