I am a survivor of sexual and domestic violence. Often, it is important to me to talk about those experiences candidly and openly with almost anyone. But sometimes, and with some people, it is scary and makes me upset to talk about sexual and domestic violence, because sometimes and in some discussions, the way those things are talked about brings me back to the time it was happening to me. It makes it hard to concentrate or engage when I'm being reminded of a really terrible time in my life.
I really appreciate settings that acknowledge when sexual or domestic violence is going to be a topic of conversation before it comes up. I appreciate when friends, professors, and others let me know what's coming, so that I can prepare to engage and concentrate on the topic, knowing that it will be a little harder for me than some other people. Sometimes, I cannot get myself to concentrate. I do not learn, and I cannot engage with the topic. I've been really lucky to be given the opportunity to step out for the day, and to approach the subject at a different time, or in a different setting, when and where I can engage with the issues of domestic and sexual violence rigorously and safely (kind of like how movies tell you there's going to be a lot of blood, because blood makes some people sick--if you're talking about war in class, you don't necessarily need to see a gory movie to engage with a discussion of war). I have never once been excused from the topic. I've never been told I get to ignore it. I've been given the opportunity to approach it differently, and prepare for it more fully, so that I can present my perspective and ideas fully. Sometimes it's as simple as seeing on the syllabus that the topic of the day is "rape," and having access to the materials that will be discussed. Sometimes it's a quick note at the beginning of the discussion. It's just giving me a head's up, and a little bit of freedom in choosing how best to engage.
That's what a trigger warning is, and what it does. When you (or, for instance, an educational institution that I happen to attend) say, blanketly, you do not support trigger warnings, you are saying that you don't care if some people engage rigorously in some topics. You are saying that you don't mind if some perspectives get left out of the discussion, because you don't want to let people prepare for hard discussions. That isn't rigor, it's not "academically freeing," and it's not something to aspire to. It's intellectually and practically lazy.