I don't see it but whatever by the definition of what dry humor is those shows don't use it.
So when Larry David is in the most outlandish situations. but the show takes the subject matter extremely seriously. just like in Seinfeld. That's not dry humor? Larry David is the VERY DEFINITION of dry humor/wit.
Or when the "there's always money in the banana stand" line is delivered and received with the utmost seriousness and not treated with even so much as a smirk...that's not dry humor? Or Tobias delivering his obviously gay lines seriously.
Arrested Development IS dry humor.
I'll find hundreds of reviews of the show that peg it as so. Even TV Guide has "Dry Humor" as one of the themes for Arrested Development.
But not according to you.
Guess I'll have to take your word for it.