The signal to noise ratio (good stuff compared to the negative stuff) on this site is very high. Very occasionally someone will raise a more negative thread but on the whole it just doesn't happen that much. With such a broad membership this is bound to happen every now and then. I think you have been 'unlucky' in terms of timing to see two such threads (negative in your opinion) in a short time.

Personally I usually just ignore it if I think it is negative. I have had no dealings with said person so I have no opinion either way.