The community here is not a random sampling of the full data set of all Nexus phones. Not even close. In fact, it's a sampling skewed to represent those that complain the most about a given device. Therefore, it can't even begin to "tell all."
Just because 100 people come here and make a post about something not working for them is not a projection about the large number of phones sold. And, in fact, for everyone saying something doesn't work there is often a similar number that say theirs does work. Followed by a punishing post by the complainers telling the satisfied group to butt out. This type of punishing behavior tends to quiet those that are satisfied so the resulting posts tend to be overwhelmingly in favor the aggressive complainers.