Good thing they had GPS back then to make such a roundup possible.
Whoops, no, they did not. No technology needed. They didn't even have databases back then.
Whether your home address is found with an old-fashioned paper map, or with GPS, is immaterial. The larger issue would be abuse of Census data, which is independent of how your address is located.
I see you already knew.
In effect, this data base makes it possible for a warrantless visual search of one's property.That includes searching with ground penetating radar as well as visual search.
The GPS census data base is just about as nefarious as it gets. The census does not need it and has no cogent reason to keep it other than for surveillance.