Why did the Jews who were conquered by the Romans survive to this day, while the Prussians who were also conquered disappeared in the 18th century?

Because Jews support each other, trust each other. We Balts, including Prussians, - no. A good example is taking away Lithuanian citizenship. History does not record, but it is possible that the last three Prussians learned something, gathered and voted to allow the preservation of the affiliation with their community, called a pulka (in Prussian), while being a member of another community. In our time, that would mean dual citizenship. After that they had a good drink (the Prussians liked to drink, like us) and dispersed. But it was already late. There were too few of them to survive.

 

And we, Lithuanians, as a community, are going into oblivion. Not trusting each other, therefore catastrophically fast.