Subject: Unlike you...
Author:
Posted on: 2016-08-17 15:36:00 UTC
I'm not a relativist. I assume (and you have to either assume this or not — it's not provable) that "truth" is objective and the same for all subjects. That's why I can say stuff like "quality has an objective facet". "Quality" is distinct from "taste"; for (fiction) writing, it includes things such as "correct SPaG", "does not break suspension of disbelief" and "within reason, keeps characters in-character".
This is distinct from "taste" — "I like this", "I don't like this". A possible reason for either is "quality", but it's not the only reason; you can acknowledge that something is bad (ie of poor quality) but still like it (like the way people enjoy The Room).
As to the whole "opinion" thing — "You shouldn't write X because it's bad" is a valid opinion and something people should hear, especially if their writing is in the public space where others can see it; saying that you should keep such opinions to yourself is akin to telling people not to tell their neighbours not to leave garbage on the sidewalk. Of course, in the interest of good etiquette, you should do so in a polite way.
Saying that something is badly written and making fun of it among your own circle of friends isn't "Fandom Police". "Fandom Police" is harassing artists who draw fanart the way you don't like to the point they try to commit suicide. Did any PPCer ever go to a Suethor and say, "you should stop writing fanfic"? No. Some PPCers do try to leave constructive criticism (to varying degrees of success) but going on and telling people to not write if they can't not write badfic is not what the PPC does. You can't tell people what to think or what to say; you can voice your displeasure yes, explain why things are bad yes, call law enforcement if the situation necessitates it, but you as a random person cannot and should not tell other people what to do.
And one last point: since you're a relativist, why are you even bothering other people by saying that your opinion has any merit? Theirs have just as much.