They're not mutually exclusive and in fact are mutually reinforcing. As readers of a comment we are expected to read it charitably and part of that is assuming that the writer is not shilling. On the other hand we expect writers to disclose major conflicts of interest and I would categorize a direct competitor as a major conflict of interest (note I'm not calling deimorz a shill and do think his/her comment reflects a common sentiment, but I appreciate the knowledge that deimorz is working on a competitor).

The latter breeds the trust for the former to work.