Yes. So there is no great answer on a bug that has accumulated vulnerable coin for 5+ years. I cannot see any way to do it right when that history already built up like that. That is probably the other thing, besides the speed at which this went from question mark to "found it", in which this is unprecedented - I honestly don't remember any fundamental flaw with such exposure time in our space. Do you?

optimism

In this particular situation users have already set up a flawed wallet. Coinkite can fix the vulnerability but as soon as they disclose to the pubic it wouldn't take long for an attacker to find the exploit and steal the slow mover coins.