Never understood why this is something people in Poland object to.
Because it's basically nonsense. If countries like Belarus, Ukraine and Russia are Eastern Europe, then Poland definitely doesn't belong there. Totally different civilisation. Central Europe consists of so-called buffer countries - Poland, Czechia, Slovakia, Hungary, Slovenia as the core plus the Baltics, Croatia, Austria and some parts of the Balkans - between the East and West. Intermarium (Międzymorze - countries between Baltic, Black and Adriatic Seas) is a separate civilisation in its own right.
As for Poland - classifying us as East doesn't make sense geographically, as there are parts of Poland that are further West than some parts of Austria or Italy. "Cultural and political reasons" sounds nonsensical too - Poland, if you look at her history, is a Latin civilisation country based on Magdeburg and Roman law from the very beginning of our statehood in 966; also, we received Christian faith from the West, that's why we are Catholic and not Orthodox today. The
44 years of Soviet domination after WW2 doesn't define well over
1000 years of our history.
That's how World Bank and OECD see the map of Central Europe...

... quite accurate. I would only oppose to including Germany in the region. You are definitely Western.