I try -- have been trying harder -- to limit how I do it.
This, so much. For me, that is really the key point to keep in mind - everyone WILL dislike some things, and that's just as legitimate as other people loving those exact same things. There's nothing wrong with hating pairing X, canon aspect Y or fic trope Z, and it can be cathartic to vent, but it's absolutely possible to do it in a way that doesn't harsh the squee of people who love XYandZ.
It's all a matter of finding the right forum.
In RL, you probably wouldn't start loudly exclaiming how ugly you find purple clothes if someone in purple were standing right next to you. You might not understand how anyone can fail to see the hideousness of their eye-searing outfit, but if it makes them happy, then good for them, right? You can freely vent about the onslaught of lavender, periwinkle and violet later on, in private, to your Purple-Free Knitting Circle. It's really no different in fandom.
Fandom is composed of a huge variety of people, all of whom are in it for different reasons. All fans will find some other fans' preferences and fannish loves weird, incomprehensible and even actively unpleasant. But that's not a bug - it's a *feature*.
I am still working on this myself! I have chosen the wrong forums in the past, and... yeah. For example, when I first started out in fandom (four score and seven years ago), I routinely gave authors detailed feedback that included what I loved about their story as well as what I thought *didn't* work, and why. My intent was to offer constructive criticism, but I have since come to realize that because I was misunderstanding the context, I was basically being a dick in some cases. (I also did this to some published authors, btw, and in those cases I would still do it - but fanworks have a different intent and expectation.)
But that's a somewhat different (if related) topic, so, yeah. Finding the right forum! Not always easy, but vital for making fandom an open space for everyone.
finding the right forum for fannish venting
This, so much. For me, that is really the key point to keep in mind - everyone WILL dislike some things, and that's just as legitimate as other people loving those exact same things. There's nothing wrong with hating pairing X, canon aspect Y or fic trope Z, and it can be cathartic to vent, but it's absolutely possible to do it in a way that doesn't harsh the squee of people who love XYandZ.
It's all a matter of finding the right forum.
In RL, you probably wouldn't start loudly exclaiming how ugly you find purple clothes if someone in purple were standing right next to you. You might not understand how anyone can fail to see the hideousness of their eye-searing outfit, but if it makes them happy, then good for them, right? You can freely vent about the onslaught of lavender, periwinkle and violet later on, in private, to your Purple-Free Knitting Circle. It's really no different in fandom.
Fandom is composed of a huge variety of people, all of whom are in it for different reasons. All fans will find some other fans' preferences and fannish loves weird, incomprehensible and even actively unpleasant. But that's not a bug - it's a *feature*.
I am still working on this myself! I have chosen the wrong forums in the past, and... yeah. For example, when I first started out in fandom (four score and seven years ago), I routinely gave authors detailed feedback that included what I loved about their story as well as what I thought *didn't* work, and why. My intent was to offer constructive criticism, but I have since come to realize that because I was misunderstanding the context, I was basically being a dick in some cases. (I also did this to some published authors, btw, and in those cases I would still do it - but fanworks have a different intent and expectation.)
But that's a somewhat different (if related) topic, so, yeah. Finding the right forum! Not always easy, but vital for making fandom an open space for everyone.