That isn't really a rule change. The lexicon just added a new preposition, 'because,' to the old list. It means almost the same thing as the old preposition 'be

That isn't really a rule change. The lexicon just added a new preposition, 'because,' to the old list. It means almost the same thing as the old preposition 'because of.' There's a difference between coining a new word and changing a grammar rule.