Could you explain further some examples of trigger warnings IRL that you've dealt with, because I assume there aren't widespread studies about this sort of thing and you seem to have a vastly different experience than mine. I'd like to understand it.
The discussion is primarily about how people perceive the idea of a safe space over the actual experience of it. I don't think it's very useful, it just reinforces peoples' perceptions of others without actually engaging with those peoples and concepts/experiences directly.
As for safe spaces, this is fine if we're talking about a room at university, but if we're talking about making a university itself a "safe space" then forget about it. It's a public place where people have to live their lives.
Religious students don't get trigger warnings for courses that treat their views as anywhere between foolish and evil. Classical liberals don't get trigger warnings for their sociology, cultural anthropology or social psychology courses, despite the fact that all those disciplines have faculty that are overwhelmingly leftist. There's a great deal of diversity of opinion in those departments but it's diversity of leftist opinion.
People aren't stupid. Trigger warnings aren't used in a way that has any correspondence to PTSD triggers. They're used as a stick to beat political opinions of the losing faction with, currently the right.