It’s not more important than others but the fact is, you’re scared of yourself.
If you’ve a phobia of flying, you don’t fly. Spiders? You can run the fuck away, clowns, I never see a clown. But when the thing you’re terrified of is something your body does, you can’t escape it.
And you’re not only on high alert when you’re actually ill. It’s all day everyday thinking this will be the day. Every bodily sensation is ‘is this it? Am I going to throw up?’ And the anxiety means you’re constantly nauseous so it’s a vicious cycle.
And on top of all this, many emetephobes develop anorexia because they’re too scared to eat in case it makes them sick.
This is just a very brief insight into why it’s so bad.
Trigger warnings help because an emetophobia brain will read this and panic that the caravan they’re going to next week will be the one it happened in or they’ll be terrified there is yet another bug going around that they will definitely catch. Both completely irrational but nothing about emetophobia is rational.
However, I do agree that it’s impossible to mage everyone’s triggers. But if you know what you’re writing could trigger someone, then it’s a nice thing to do to give a heads up.