I don't have a problem with the T-pain style of autotune. The worst form of it when it's used on every single note without the ridiculous note-snapping effect that makes it so obvious
I could come up with a thousand examples, but I remember when I was in college and listening to a lot of 90s music. Blink 182 had this album come out, and I couldn't even listen to 3 seconds of vocals because of the insane amount of pitch correction grinding the life out of everything: