1. People give the information to the government under the expectation that this data is to be kept private or used in such a way that individual targeting is made impossible, you break that expectation and people will lie or won't give you this data.

2. Without noise injection it's rather simple to do statistical attacks to reverse engineer individual entities.

3. This data is and has already been used in the past to undermine democratic systems by targeting and disenfranchising minorities, as well as gerrymandering the US to hell.

4. "Too dangerous to make public, too dangerous to collect" - this is a false dichotomy. To govern effectively you need sensitive data, but it should be collected and used in a way that's safe for the individuals.

5. Macro level aggregates don't need individual exposure, that's why noise, anonymization and statistical functions are fine.