The advantage to prescriptive rules for language is that you don't lose the context of a language over time or distance. My hope was that the popularity of the web would make it easier to communicate and understand each other, and also that languages would mature to the point where we could read historical documents without a language barrier.
Instead, it seems like language in popular use seems to have evolved more quickly, we're not as good at communication as before, and we collectively choose our words less carefully out of a smaller pool.
Or maybe I'm just getting old and cranky.