At that moment his sneakers feel horribly, horribly overcomfortable. Maybe you’ve experienced this sensation. You’re riding on a commuter train, and all around you people are in business suits. In this context, your casual clothes feel ridiculously soft and easy. You might as well be wearing pajamas. The comfortableness hangs on you like a cloying hug.
Source: wiktionary
The “over” and “under” prefixes, however, seem only to be applied to things that we, as a culture or collective, determine to be tolerable in the first place. Each prefix transmits a deviation in what is or can be tolerated. For example, when was the last time you heard a KKK member described as “overracist?” Why don’t we speak of law-abiding citizens as “undercriminal?” When was the last time you spoke of “underviolence” or “overcomfortable?” The “over” and “under” is only applied to those things we already understand as manageable or expected.
Source: wiktionary