Warsaw as most of the eastern part Poland is still heavily influenced by the post-Soviet mentality. Warsaw is even less diverse than ~380k-headcount Lublin (also eastern part) due to Lublin's universities welcoming international students with relatively cheap living costs for years now.

I live in Poland for 40 years, I'm biased, but I'd say that if you're looking for "western" cities - it's not Warsaw but Gdańsk or Poznań. Warsaw will keep its post-soviet mentality at least until the generation remembering WW2 is alive. Of course younger people may lack exposure to it, but I'm generalising on city/region-level.

I'm just solely going by developmental metrics and median household income.

Eastern Poland might have a fairly conservative society (as is reflected by Sejm and Presidential election results), but because Warsaw is the political, financial, and social capital of Poland, social and economic infrastructure is much stronger there than in other parts of Poland - west or east.

It's the same way that Beijing is luxurious but very socially conservative compared to Shanghai.