This is tangential to your point, but I'm pretty sure what you're referring to isn't being "triggered." It's, I don't know, disagreeing? It has a specific and important definition, and it seems to be getting thrown around in other scenarios, to the detriment of those with PTSD.
[1] http://www.dictionary.com/browse/triggered
[2] https://www.urbandictionary.com/define.php?term=Triggered
>to initiate or precipitate (a chain of events, scientific reaction, psychological process, etc.)
"Psychological process," in this case, is what I was talking about, and what I think the original commenter was referring to. "Trigger warnings" aren't warning you that you might feel "anything that will cause a reaction," they're to help people suffering with PTSD avoid having a panic attack.
I agree that the colloquial definition is trending the way you describe, and I think it's irresponsible to just sit and watch it happen without speaking up in favor of the more specific psychological definition.