The gist of this article seems to be, from my perspective, that Powerpoint should be diagram-heavy and word-light, to avoid cognitive overload. That is, it is highlighting tool. Shouldn't try to cram too many words into the presentation.
I’ve found that I get a lot out of a very wordy PP presentation when I’ve downloaded and reviewed it myself.
Many people write a full paper instead of a simple outline when they do a PP ... This can be good.
However, it is true that when such is being presented, the speaker can cause information overload and confusion while I’m trying to spend time figuring out the last slide that I would have liked to hear more about.