Probably: "We used that code, and it harmed us in some way (e.g. we had to give someone money for something). You wrote that code. It is your fault. You have to pay us that money now."
All of the liabilities I found for open source software involved intellectual property cases.
Are you aware of any cases where this has actually happened? Because, if not, it sounds more like the standard boilerplate disclaimer that lawyers tell you to include just in case anyone ever does try such a thing, rather than a protection against a thing that has actually happened.
Ie. you have an old phone that seems to work but choose to just give it away because why not, then someone loses important info when using the phone because it's old you are not liable for loss of that data.
Any intentional backdoors or on purpose data destruction are are not covered by licenses anyways since you are acting in bad faith when doing those.
> Surely such a claim would be thrown out in court and then all cases such after would be dismissed with prejudice, meaning the judicial example would already exist.
Afaik not all courts all over the world work that way, besides of course there being hundreds of courts with different rules that all would have to go through that at least once for a creator to be able to rely on that.