Fandom can't simply "suspend" something like that in a real space (the internet is opposed to "real life" because it's virtual, not because it's not real, as in, doesn't exist). The right of protest or any human right can be suspended in a piece of fiction, sure, but fandom is not fictional.
If somebody wants a fictional space in the internet, a bit like a RPG, where criticism of any kind isn't valid then they can create it but the assumption that fandom in general is such a space is absurd. If something differs from the norm then you have to let people know about it, and in a community there should be agreement about it and there’s been so many bouts of disagreement about this, not just about things like Racefail but individual fans like furiosity and outlangi who wanted to be able to criticize fanfiction on the grounds original fiction can be criticized without being thought to be attacking anybody (and always offering the chance to the author to say they wanted to be in a fictional space without criticism).
And in this fictional space, where the normal RL rules don't apply there should be some kind of proper warning like "we don't accept any kind of criticism" or even "squee only", that's to say, non-charged language like "hate" but an unequivocal statement of intentions. That said, most of the time I feel like constricted by this implicit rule of "no criticism in fandom" and don't bother. And sometimes when I bother, because maybe it's a critical post I'm against, the fact that fandom doesn't have a widespread habit of criticism often makes it seem as if the critic is attacking (in the middle of all the fluff and squee any disagreement can seem harsh).
That said, and going back to the warnings debacle, I don't think anybody has to think about what others will feel when they read/see their art if they don't want to, I do but that is also a choice, proper warnings and all that are very nice but they are not a must. What is a must, for me, is freedom. I have often flinched and more while reading fic or fandom posts but I know someone wrote those things because they are meaningful and enjoyable to them and it's fine, and I, in turn, should be able to tell them "you should use a spellchecker" or "I don't think this character would ever do that", neither their writing nor my writing is in itself an attack and shouldn’t be interpreted as so as long as they are reasonably and politely worded and their intent is clear.
Nobody has to be careful of what they say because it might be hurtful, they probably should try to but it’s not an obligation. What is it’s to give others the same right to speak freely, even if it hurts you.