I hate the "Holocaust census data" argument because presented like this, it can be used to demonize pretty much anything. Yes, Nazis used census data because it was available. Were it not, they would've used something else. When a band of monsters with resources of a country wants to get you, they will get you. You have to consider the possibility of it, but in times of peace, it's no way for living. Census data isn't collected in anticipation of future monsters in power - it's collected to provide immediate benefit to citizens.

The right answer is not "this dataset shouldn't exist" - it's "what benefits does this data give us, and do those benefits outweigh the risk of abuse?".