I fear you are correct, and that there is no meaningful solution to this problem, but the real problem for you as a society is that the senseless killing is going to get progressively worse to the point where all the things that make America such a great place to live will diminish to a point of insignificance. I can’t see any other pathway.
And if 2A is truly immutable, then I can see no possible long term outcome, if that tragic path is traveled, other than some States eventually seceding from the Union. Some people, in some States (on each coast) will eventually say ‘enough is enough’.
I must confess I find the evangelical and slavish adherence to 2A to be nothing short of bizarre. Its wording is plainly anachronistic and incongruous with modern legislature. It expressly mentions regulation and yet its fiercest acolytes are inimical to any associated meaningful regulation. It seems an utterly absurd thing to build your belief system around, but as you say it’s not going anywhere, and any moves to do so would be met with widespread and violent civil disobedience.
Sadly I think it will eventually be the downfall of US society, and there’s nothing anyone can do about it, other than watch in horror.