Can you sue a bank for having bank holiday before capital controls come in place? I don't think so. Core devs are not a bank of course but this argument is stupid so I'm giving you a stupid analogy. OP almost sounds like a troll.
Correct analogy would be sue a bank for not executing your tx and next day go bankrupt so that your money is lost.
Hope you do not troll me?
Then in your case the right answer would be that it's not the developer's fault. It was your choice to use that exchange, and
as long as no transaction left the wallet it was the fault of the exchanges wallet that you didn't get your coins. The most likely scenarion though is that there would be a transaction leaving the wallet, just not a transaction with high priority due to faulty fees.
Legally, this answer above is most correct.
If the exchange sent a tx to your non-exchange wallet, and due to an insufficient fee it does not get included in any block,
the tx will be returned to the exchange wallet. In the mean time, if the exchange went bankrupt and shutdown, it would be
the exchange that would have your money and you would have to file with the bankruptcy court.
The argument that the Devs would be legally responsible for such a situation would be an incorrect legal theory.
It is important to remember that Bitcoin is still an experiment in many different fields, and as such, is still
considered a "use at your own risk" by governments and the courts. The Courts would advise that you file
any such action against the exchange, just as you would against a bank.
