The problem is that you can't take the data back when good organizations turn bad. Maybe you trusted the US government in 1940 when you took the census, but in

The problem is that you can't take the data back when good organizations turn bad. Maybe you trusted the US government in 1940 when you took the census, but in 1942 they showed up at your door to take you away if you had listed yourself as Japanese. If you lived in the Netherlands in the 1930s, you may have had a great deal of trust in your government. They collected extensive population data and did a lot of good with it. When the Nazis invaded, they got access to the same systems. It made their genocide much more effective than in neighbouring countries.