How much more outright case law proof that Heller is not sweeping existing gun control away does it take for it to be accepted anywhere but on the right? How many dozens or hundreds of gun control laws holding up post Heller makes the truth of it’s limits visible?
Heller took away the worst fears of the far right on guns, as they were thought to be subject to confiscation until the 2nd got upheld as an individual right. Sadly attacks on that ruling have seriously diminished confidence in that landmark ruling. Every powerful voice that calls for a new SCOTUS to overturn it contributes.
OTOH gun rights critics could point at Heller, explain the confiscation/ban fear has been put to rest by that ruling and now we need universal registration. Advertise the legal strength of Heller, start a voluntary Federal registration system to apply peer pressure from the bottom up. IOW be reasonable, you got a huge win. Enjoy it. End the bans, have a purchase/transfer process that’s fair and strict.