These terms have several meanings and are fuzzy.

Most commonly people in Europe still divide the continent between Western and Eastern Europe and Eastern Europe roughly means former communist countries.

So most people in 'Western Europe' will include Poles among Eastern Europeans (which may be pejorative depending on context).

I think that sometimes those pushing for the term 'central Europe' do so because they don't like being lumped into the same 'category' as their neighbours further East...

Poland and Czechoslovakia were part of the Soviet Union and as such their successor states are still considered part of Eastern Europe by (many) people living in nations on the other side of the iron curtain.

This has more to do with culture than with actual geographic location.

Oddly enough the centuries of shared culture before that didn't have that impact.