Presentation documents can never do double duty. They will always fail at least one of the goals, and if you insist on not optimizing for one, they will fail both.
Most routing corporate stuff is just people booking the time for denying others the excuse to say they didn't know about it because of time constraints. Those people don't care if the presentation fails to communicate anything (what it almost always does).
Most routine corporate stuff is basically a document in presentation form which a lot of people seem to prefer these days. Yes, you may give a 30 minute "presentation" using the "slides" but it's not really a presentation which I think is fine. I don't really disagree with your basic point. The sort of thing presented at larger team meetings I attended latterly tended to FYI sort of stuff, some of which was vaguely useful to know and some of which wasn't.
Most routing corporate stuff is just people booking the time for denying others the excuse to say they didn't know about it because of time constraints. Those people don't care if the presentation fails to communicate anything (what it almost always does).