The previous owner must not have used them much. I've got maybe a few mm of clearance on the top of my giant noggin due to how permanently squish those pads are. Please let me know those replacements go, the ear pads are equally squished on mine. Should probably replace both.
Oh, somewhat related question. I replaced the absolutely filthy pads my old DT 990 so my son could have his first pair of decent headphones. This was my first time ever doing this and the screwdriver slipped while get the ring off and I poked a hole in some sort of paper. I know larger speakers use paper drivers but headphones don't, I think? What did I puncture? I put it back together and seems fine, but hearing is subjective.