Part of the issue is that members like to pontificate about ideal conditions for each species, but real life isn't ideal. Knowing what space and tankmates a species should have is something I/we should all try to educate ourselves on when considering a purchase, but many new members find themselves with fish in less than ideal tanks prior to knowing better. I have been guilty of this and would be willing to bet most everyone here has. Even the most seasoned fish keepers with decades of experience started in the same place, though some seem to forget that. While we all should strive to give our fish the best we can, educate ourselves, and research prior to getting into bad situations, no one here can say that their fish are kept in the most ideal conditions meant for health and well being. We keep fish in glass boxes, no fish's ideal conditions. If we all cared for the absolute perfect conditions for our fish then we wouldn't keep fish. We would boycott the industry and this forum wouldn't exist. Hard truths. But we do keep fish and its great to have a place to ask others for help and advice.
Remember... if people didn't care, they wouldn't be here asking!