If you'd lost an inhibitor yeah you'd be justified in surrendering. Otherwise I've seen worse scores turn around.
Given that you started the surrender vote though I'd guess you were actually the worst player and blaming the Yi because he was the second worst.
At least that's what I observe as the usual in games where only one player wants to surrender.
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I tried to have a fierce rivalry with SuperNiceDog, but he made me look worse than a GameFAQs Contest!