What's the best word for the type of humor where you state something very honestly and bluntly with the intent to be a little shocking and a little humorous? Potentially because people don't expect a certain behavior to be pointed out so bluntly? It's not sarcasm because you are telling the truth, right, not the opposite of what you mean?
That description brings to mind "bluff" as an adjective to describe that kind of humor:
1. good-naturedly direct, blunt, or frank; heartily outspoken.
Bluff humor: it's honest, it's blunt, it's frank—but it doesn't have the negative qualities of some other, sharper adjectives, and it doesn't shade toward sarcasm or mockery. And such outspokenness can certainly be surprising.
mordant Collins adj
Mordant humor is very critical and often mocks someone or something; harshly ironic or sinister
- Of a person, his or her wit, a remark, etc.: having or showing a sharply critical quality; biting, caustic, incisive.
"A mordant sense of humor informs many of the scenes, as when Georg asks for a room and is told by the landlady that he must produce papers proving his travel plans." Seattle TimesApr 2, 2019