Yes, the triggers produce emotions, but not because of the art alone, but because the subconscious memories are facilitated into the conscious by that art. In practice its a negligible detail, but still interesting to think about.
I mean, for instance, let's take a comic that's completely unrelatable to a lot of people, some girl power comic that shits on men, right? It's made for a certain kind of audience that has a certain kind of life and a certain set of memory memes in place from the community they set themselves in. If you're not in it, its not like america chavez is gonna make anyone cry, or some YASSS QUEEEEN blowing the fuck out of some dude.
But what emotions does it trigger in people? The emotions associated with memories of that community to a lot of people here, which ranges from annoyance, disgust, anger, generally shit that makes you less ready to go "oh these beautiful pee oh cee smashing the patriarchee!", and more ready to reach into the "this is shitty writing and I hate these characters and these smug people" memories.
the main thing I'm getting at is that art is subjective because of memories, art is subjective because people are subjective, and it's a little pernicious to think art in and of itself will always illicit emotion without a larger context of psychology and cultural memories.