No Spoiler warnings are important. Trigger warnings are important.

What is wrong is when people use Trigger warnings all the time and for stupid shit.
If you get angry when you see the color blue, that isn't something that should be Trigger warninged. What should be trigger warninged is intense war, depictions of suicide or self mutilation, and a few other things. Things where if a person sees them, it could threaten their life because they are "triggered". Someone with PTSD from war and battle might physically harm themselves or others. Suicidal people might kill themselves if they it.

Actually, I expect spoiler warnings on things that might ruin my experience of a movie, book, tv show, game, or whatever.