At that time fans/media ignored, weren't aware of overestimated Dwight's low post "skills" or lack there of. You really just needed a big guy who wouldn't get muscled deep in the paint to guard him straight up. Today's nba doesn't have many of them worth getting time. But that's very different than guarding skilled guys like Gasol and Bynum. Perkins is a good defender, but not as good as he was made out to be bc of that.
If you consider good role players under rated then we don't really disagree. I feel Perkins was hyped beyond the "good role player" level so can't consider him underappreciated considering that. I think Battier is a perfect name for this discussion.