We have had a gun registry for many years (make work project by goverment)now and i never registered mine.
The main reason is some of my rifles have been handed down generations one from my grandfather he used in WW1 and this is all i have from him.
Australia decided to outlaw guns in their country years ago and started rounding up all the guns and destroying them and for a lot of people they too had guns passed down hundreds of years.
The registry here has not done anything to stop gun violence as the people who register the guns are not the one using them it's the criminals and guess what they won't be reporting theirs.
They now have a program here turn in your guns and get a camera
if people want to do this that's their choice but at least they have a choice.