I don't think I've ever heard the absurd levels of this blog post and I've lived in few expensive cities from italy, poland and switzerland, where it is impossible for middle class locals to live there.
Locals have a much lower income than Italy or Switzerland. Thus they are still getting priced out of cities where they have lived a long time. In Warsaw the locals are often priced out by the returning diaspora. See Lebanon, parts of Italy, Ireland in the past, etc.
Currently I think it's quite expensive (for locals). E.g. bedroom + living room costs > 3k PLN in Cracow, and probably more in Warsaw. At the same time junior dev can earn about 5-9k PLN net. My non-dev friends often are not even able to live in Cracow.
