Natural language generation

Suppose someone says - 

1. Who trained the smartest man in the world, to be the smartest man in the world?
2. There are -3 people in this room. 

Now, both the above statements are perfect in English. But they are meaningless. No one trains someone to be the smartest man in the world. And there cannot be -3 people anywhere.

They are untrue. They are impossible in the real world. But they still can have existence in the real world other than the obvious alternative of saying that maybe they are true in some children’s fictional story. And that is, that - someone said them. That provides a perfect legitimate context and background in which they can exist in the real world.

Thus, anything which is grammatically perfect will carry a possible context in which it is “meaningful”. If something is “CORRECT”, i.e. according to some set of rules, then it has an existence. 

What about grammatically incorrect sentences or things which don't satisfy any set of rules? Do they have existence? Say, ‘John apple 5’. This isn't correct English in the first place. But one can say that while illustrating a point I mentioned it as an example and ultimately did type it - in which case, it gains a context of existing in the real world. 

So does anything, that is generated by a language-capable entity, have an existence in the real world? Yes - other than being out of "validity", either out of an illustration/mention or a mistake or insanity/deficiency of the mind.