We are having a similar debate here in NZ following the Christchurch tragedy. The government quickly introduced a ban on automatic weapons and will introduce gun registration. The pro-gun lobby trotted out similar arguments about criminalising law abiding people and suggested criminals wouldn’t bother handing in their weapons or registering them.
Surely the point is that everybody that registers would potentially be off the list of suspects and the authorities will only have to spend their time dealing with the small percentage that don’t comply with the regulations.
Those of us with steam engines join a club and pay subs so we can get our boilers tested and approved for public use. We do it because we have to if we want to be safe and be insured to use them in public. Surely its much the same arguments for model aircraft?
Pete