Then, “standard” shouldn’t mean mandatory, only “if you want to express something like this, use this keyword; also look at the list of keywords to find things that may be useful for your article”.
So, if your articles doesn’t need trigger warnings, don’t use them. The word is there because (1) it is sometimes useful, (2) it may be useful to remind authors to consider whether it is useful, and (3) so that all authors that want to express this kind of idea use the same label for it, making it easier for readers familiar with the convention.
Then, “standard” shouldn’t mean mandatory, only “if you want to express something like this, use this keyword; also look at the list of keywords to find things that may be useful for your article”.
So, if your articles doesn’t need trigger warnings, don’t use them. The word is there because (1) it is sometimes useful, (2) it may be useful to remind authors to consider whether it is useful, and (3) so that all authors that want to express this kind of idea use the same label for it, making it easier for readers familiar with the convention.