There's this running joke among writers about the haiku. Haiku are apparently so easy any good poet shouldn't be focusing on them if he wants to get anywhere in his career, or if he doesn't want to be the butt of jokes. Try to introduce yourself to a group of Filipino literati by saying something like: "Oh, I write haiku" and expect to be met with silent giggles or evasive looks.
This is just my observation. And honestly, I'm not sure if they make fun of the haiku form because they don't understand the Zen Moment required to write a good one... or if they simply don't have skill in the short forms. Of course, making fun of something you don't understand is the easiest way to get out of having to write it. It's easy to say "I don't write haiku because it doesn't make sense most of the time." "No one can or wants to make sense of haiku anyway."
Different strokes for different folks? I'd personally stop commenting on haiku and tanka writers and their work until I fully understand the intricacies of those short forms.