It can't be more silly. I think those people should not even be called as hackers since even an average bitcoin holder knows that brute forcing a wallet is a complete waste. If it were to be a real hackers then they would rather try finding and compromising the device on which the wallet was previously used and then decrypting the private key from the device. Anyway, articles like these have been previously posted on this forum but nobody actually got anywhere with brute forcing.