We require licenses to prove people are competent to operate a motor vehicle and we require most motor vehicles to be registered. Yet, car confiscation isn’t a huge issue in this country.
In fact, some states already have licensing and registration laws for guns and they’ve also managed to not tumble down that slippery slope.
I‘ll grant that some people do want to confiscate guns, but that’s not a popular view. See https://news.gallup.com/poll/1645/guns.aspx.