Ok, maybe that's a generalization, but apart from really really intense For Your Consideration campaigns or public pressure (e.g. Robert Downey Jr for Tropic Thunder), comedies and comedic films in general are overlooked when considering "good" acting performances.
But if you can tell me with a straight face that Vincent D'Onofrio didn't convince you he was a bug alien in a human body in Men In Black, you're crazy! Legitimately an unbelievable performance and it should've been acknowledged.