Effective rhetoric takes into account its audience. Because of their positions and the gravity of their speeches, none of those leaders could really have hoped

Effective rhetoric takes into account its audience. Because of their positions and the gravity of their speeches, none of those leaders could really have hoped to cuss in them. But it wouldn't be surprising in the least if they did when discussing certain matters with others, for example (obviously it depends on the person). Presenters who cuss and are actually good presenters have made a decision that their audience will deal with cussing, and therefore it is a stylistic flourish they can use. Now, they may be wrong—but a few blog posts don't prove that. People no longer being interested in their presentations prove that.