You can’t lie to them, but they can lie to you all day long.
The government way
Many gun owners routinely sell firearms, in order to purchase something different that better suits their needs. Even more gun owners move every five or ten years, or change their names, or give firearms to family members. And of course, there are deaths (with associated inheritances, official or otherwise), and thefts, and simple typos on the paperwork. Attempting to generate a usable registration database from decades-old 4473s is not just illegal - it’s a fool’s errand, and a complete waste of the taxpayers’ money...