Writing itself is aggressive, and I'd posit that any sample of good comments is going to skew negative in perceived tone - or use implied negativity as a ground to the positive comments figure.
I'd even say the agreeableness that makes for sustainable modern office relationships is not a quality that makes for insightful writing. It can coexist, but it's a different skill, so I don't interpret good comments as negative. Predictable talking points, that's most of what one needs to know about someone, but original writing whether I agree with it or not is usually worth considering.