Do we need to prove that any given problem is unsolvable, or is it enough to remove broken tasks from the training pipeline? I understand the broken benchmark

Do we need to prove that any given problem is unsolvable, or is it enough to remove broken tasks from the training pipeline? I understand the broken benchmark task in the HF incident was conceptually like: "Exploit vulnerability 0042 in vulnerableDecompress() to obtain the flag". But instead of the expected: const output = vulnerableDecompress(userInput); return output; The grader had something more like that: const output = vulnerableDecompress(userInput); return 0; The same kind of problem with broken tasks exists in the training pipeline, and we presumably reward workarounds and hacks that tamper with the grader, rather than rewarding the correct output that the task is not solvable.