The Commerce Clause is the dominant law.
The ACS is not an unusual search under the Fourth Amendment. You are not being penalized for any answer you give to the Census Bureau.
Modern societies need this information; I know from having been there that the identifying information is stripped from the ACS. No one who gets the data knows from whom it came from. It may be annoying but it’s not unconstitutional. Sorry.
Sorry sir, but you are as faddish — in a bad bad way — in the Law and understanding of the Law and the Constitution as was the outstanding Jurist Roger B. Taney in his time. Just as in that sad sad time most of the elites of US Law either agreed in principle with Tanny in Scott, or agreed to accept it as settled law, so to do you and many of the modernity in law accept or hold by a very flawed understanding of the rights of men, the right to be secure in our persons, places and effects.