Reminder: US Census data has been misused twice in the past. Once to locate and imprison people of Japanese ancestry in internment camps in WW2. Once to locate and harass people of Middle Eastern descent after 9/11.
These are only the incidents that we know of.
Census data is only protected by flimsy federal law and "policy." The security of your census data is not protected by the constitution in any way. The problem with this is that Congress can rewrite or rescind these laws and policies at any time, even retroactively. Many of the questions are not coincidentally specifically on topics that Republicans are for some reason fascinated with — race and gender, spoken language, income brackets, etc. This is obviously a ticking time bomb to anyone with a functioning brain, and the historical records are mitigated somewhat only by the fact that the census is taken only every 10 years and the location data probably becomes obsolete fairly quickly. The obfuscation method described in the article has only been used once, on the last census. Presumably the data from previous counts, not to mention the next one, would be out in the open the moment any insane politician writes themselves a law enabling them to access it (or they just choose to ignore the existing laws and procedures, knowing full well no one will actually stop them).