@XenoBladeX37645 Ok, going to go into a bit more detail. I'm typing this on a phone so it is a bit annoying to type long detailed posts.
In regards to the MW2 comparison, adding something before a cutscene plays would require flagging every cutscene with either needing or not needing the warning, unless you hard code it in specifically for the scene, which is likely closer to what the bath scenes do. Without flagging each cutscene, the game will return a programming error when it looks for the flag and doesn't find one.
The issue with the hard code method is that you have to hard code it for each cutscene. This might be easier to do with new stuff since you can plan for it, but it is harder to do after the fact.