It’s a trap.
Two words:
EMP.
Electromagnetic Pulse.
Police are already using it to disable cars (with only spotty success, but its a new technology). Older cars with no sensitive chip technology? Impervious. This could be modelled on “ Cash for Clunkers.” We’ll let you trade in your dangerous old guns for these shiny new “smart” weapons, because then when we come for you we can just turn your weapons off. Neat trick. So the only people buying “smart” guns will be, well, not so smart. To put it politely.