If you see a NSFW game when you don't have that box checked or aren't searching for those games, the problem is that the developer hasn't marked their game as NSFW. What you should do is report it to staff or notify the developer.
No matter how many automatic warnings are created, if a developer doesn't indicate that their game contains NSFW content, it's impossible for a script to provide that information.
EDIT:
I forgot, but the warnings you suggest already exist.
