I am utterly surprised that the page quote isn't the Crispin's Day speech. Do people really think a mere video game quote is a better example of a Rousing Speech than that?

A seperate trope for De-motivational speeches?

Sometimes, I've seen this trope subverted very strongly. In Knights of the Old Republic II, when asked to set up defenses, you can sabotage various things, including a speech to the defenders.

My favorite part of that speech is when the protagonist can say that it really hurts to be shot between the legs, so try not to get shot!

What do the mythology examples have to do with speeches? Are they on the wrong page or just very poorly explained?