You're exactly right. This is just leaving out the "of". The article interprets this to mean that the word "because" has become a new preposition used in plac

You're exactly right. This is just leaving out the "of". The article interprets this to mean that the word "because" has become a new preposition used in place of the proposition "of". Another interpretation is that "because" retains its grammatical usage but a new sentence structure has become acceptable. I personally interpret it the second way. Each domain has its own grammatical structure.