I don't think that they've earned the benefit of the doubt here, but I think it goes too far to say that there's no reason why benign diagnostic software might

I don't think that they've earned the benefit of the doubt here, but I think it goes too far to say that there's no reason why benign diagnostic software might pay attention to key presses. For example, a particular button combination could bring up a diagnostics screen or send additional information. The logging, likewise could be just some debug code accidentally left in.