good points. I agree that when there are MULTIPLE English speakers in the group, it's almost impossible to slow them down. I also agree that it's unlikely to be arrogance in that case.
Perhaps I was mostly referring to one-to-one communications. I think there's something specific to English though, especially the pronunciation part.
As an example, I have heard multiple times from Japanese and Russians that learning how to pronounce Italian is quite simple for them; I also was often in situations where Italians were thought to be Russians because of the way they would pronounce English.
This means that some languages are easier than others, and I still think that English is not that great from this point of view.