TL;DR: This video is fine. There's a part about not saying Thank You at the end of speeches that I like. Other than that, I didn't get much out of it. Skip to 57:42 if you want to see that part.
I watched this video from MIT OpenCourseWare title "How To Speak".
The first part of it was fine, but didn't hold tremendous resonance with me. What I really liked was the end where the professor talked about how to close a speech.
The professor recommends against opening with a joke. Closing with a joke gets a pass though. The professor quotes a good speaker they know as saying that closing with a joke makes the audience feel like they've had fun the whole time.
Discussion of saying "Thank you" to the audience is next. The basic guidance is: don't do that. The conceit is that it implies that the audience is doing you a favor instead of doing something else they would rather have been doing.
The alternative they provide is saluting the audience. For example, talking about the pleasure of being there and seeing what they've been doing and how you look forward to seeing what they do next.