I think my main problem with meowrails being seen as good is that it's only possible if you make both characters less interesting. Though I do wish she was more fleshed out in Homestuck, Nepeta is an interesting character to me mainly due to her being the most rebellious of the trolls (at least based on your first impressions when you meet them all). This makes her relationship with Equius interesting, but mainly in how this inevitably leads to conflict between them and starts to show how her motivations can be bad for herself in the long run when it comes to other people. On Equius's side, I find him interesting as a character who has taken the path of least resistance by slipping into his culture's bigoted views because they put him above most other people. This interacts with the fact that he has developed empathy and friendships with people he considers lesser an interesting inner-conflict for him. It also makes most of these relationships pretty terrible for the other people in them. I like meowrails for how it informs these characters, but that only works if you are understanding that it is not a healthy relationship.