Neither the FBI’s NICS system nor the various state systems are set up to handle inquiries from private citizens.

Yep. If a universal NICS system was set up for peer to peer sales, it would have to be online by its very nature, and accessible by private citizens by its very nature. If not, it couldn’t achieve its intended function, so it would have to be a new thing regardless, and would have to supersede (or be an alternate to) state systems. It’s the only way national UBC could ever exist in the first place.

So at that point, you can set it up however you like. You can set it up with a registry, or without a registry. It could be “I log on and print out a gun buying license to show to people” and that’s that, for instance. Just because existing UBC laws have been formulated one way does not mean that that’s the only way to formulate them, to achieve the efficacy Siegel identifies in his studies.

In addition, there is a huge gray area involving what constitutes a “transfer.” You may think it’s the sale or gift of a firearm or a similar commercial transaction.

Well sure. You could just get the person you’re two which you’re gifting the firearm to run their check to receive the gift.

However, in the Bipartisan Background Check Act of 2019, transfers included loaning a rifle to a friend for a hunting trip without any expectation of any compensation at all. In fact, even handing a gun to another person at a shooting range is a transfer. So is loaning a gun to a person who is concerned about a stalker or jealous ex.

That law is stupid, for those reasons and more. The biggest reason it’s stupid is because someone with suicidal thoughts can’t entrust their gun to a buddy.