I think there are some people out there who are really personally invested in this idea that you can will trauma away. If they don't talk about it, don't think about it, and just pretend it didn't happen, then the effects of the trauma don't exist. Then they need to imply that people who can't/haven't adopted this strategy are somehow not trying hard enough in order to shore up the idea that trauma is completely controllable. So maybe consider whether the person telling you this has their own complicated past that they're trying to deny exists to everybody including themselves. I don't think the science at all supports what they're saying.

Nobody would say that a combat veteran with PTSD is just choosing to be triggered by fireworks. The same is true for people with C-PTSD. It's just that the triggers tend to be more subtle.