AFAIK it's a cultural / historical delineation, not a geometrical one. Kind of like how the "US Midwest" is actually mostly in the eastern third of the contiguous states. AFAICT the boundary is roughly the eastern border of the Holy Roman Empire.
Well I guess if you live in the middle, then just having East and West aren't quite sufficient to describe locations -- where's the dividing line? -- so you need an idea of what's central; and people will tend to think of themselves as central.
I mean Czechia/Eastern Germany/Western Poland is pretty much the centre of the land-mass from Ireland/Portugal in the West to Ukraine/Estonia in the East. So, it's not wrong.
Eastern and Western Europe is a commonly understood in American media. Central Europe is not. Whether you’re in East or west depends on which side of the iron curtain you were on.
This distinction was relevant for a mere 45 years, a period which ended almost 30 years ago. It's time to get it over with. The Czech Republic is about as Central European as it gets.
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