There's an interesting coping mechanism (verging on the conspiracy theory) popular on some Polish forums, namely that the abysmal data comes from abundance of sensors combined with them being placed (by whom and why? here's where the conspiracy part kicks in) in the most polluted spots.

Here's a debunk by a popular Polish fact checking portal (in Polish): https://demagog.org.pl/analizy_i_raporty/smog-nie-taki-zly-j...