Simply not true. Licensure and registration exists in several states - and have not led to confiscation. Countries like Switzerland, which have long standing traditions respecting both the shooting sports and self-defense, nevertheless require licensure and registration - again without confiscation.
But this is not 100% of the time, in 100% of the cases.
Switzerland is unique among European countries,
and you know this.
Other European countries require Licences and registration for gun ownership, but do not actually allow the gun owner to keep the firearm at home.
It allows the "owner" to kept their firearms in a government sanctioned gun club, where the owner may "visit" his firearms from time to time, rendering the whole idea of "ownership" in these countries as useless and preposterous.
So, you can draw the conclusion that most countries that require licenses,registrations, and insurance will not be like Switzerland. They are not
now like Switzerland, but rather like the gun club example.