I don’t. The text you quote was intended to show that the concept of “not existing at the same time” is nonsense/meaningless.
Well, apart from Dr Who being fictional and you being “there” and me being “here”, that was the point I was trying to make.
But we may all measure time differently.
Define “exist”.
Define “at the same time”.
But, in general, you and me and the Internet “exist at the same time” otherwise we would not be having this conversation.
On the other hand, The Titanic existed at a different time, which is why I am not crossing the Atlantic on it.