I wonder why people are making an issue of deaths of just about anything. At least these days, and with a groups of people far away from their own lives.
Short term memory I suppose. After the end of the Second World War, people from Poland, the Czech Republic and The Slovak Republic left by the hundreds of thousands the result being that many of the cities were under populated for decades.
It also happened in Hungary and Romania. So, the effect was wide spread.
They were all ordinary people, whose only common link was that they were Germans, at least by their origins. All of their unique cultures are now extinct or almost extinct.
Where is the History? In oral traditions