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.