I'm late on this one, but my submission for things that have always actually sucked is Mel Brooks. After his recent bout of publicity, I was inspired to have another look at Young Frankenstein. Besides the production design, it is awful. It moves at a snail's pace, the jokes are incredibly corny, and most of the gags are telegraphed from a mile away. And he's always been awful - the 2000-year-old Man? Joyless.
Even as a kid, I could tell Spaceballs was idiotic. It's as though he makes kids movies, but they're too bawdy and tasteless for kids.
The Producers is the only exception to this that I am aware of! It's pretty funny.