that is basically how all large companies behave anyway. socialize the losses (bailouts, layoffs, negative economic impacts in the communities they reside, etc.) and privatize the gains.

Why do you assume banks would keep on doing the same old thing but paying more because of it? The cost would make them learn not to design systems where something like this hypothetical scenario was possible.

Linux was informed properly, and the vuln was not disclosed until 30 days after the kernel was patched.

The real debate here is what went wrong with getting that info downstream, and whose responsibility was that?

Respectfully, I don't think they're missing the point. Banking, as an institution, has its flaws, but deposit insurance isn't one of them. These vulnerabilities exist whether or not they follow specific disclosure rituals, and systems should be deployed with defense-in-depth so that one privilege-escalation flaw is a recoverable event. Inventing tortured counterfactual analogies doesn't change the basic thrust of the poster's point: the account is insured, so getting drained by an attacker is not a fatal problem. Of course people should still take steps to prevent that from happening, but that doesn't mean prevention is (or should be) the only cure.