I do have a bizarre need to be over-levelled in a lot of Final Fantasy games specifically, and weirdly, I don't really have the issue in a lot of other JRPGs. It also depends if there is fun side content, too. I'm not sure if it's a 'hey, you should be at this level!' 'You can't tell me what to do, you're not my mother!' kinda thing. In a lot of earlier FF games, I think it was my hatred of random battles that would leave me taking the time to over-level so that I could steamroll through them. FFXIII's levelling was a bit funny in particular, as it would lock down parts of the crystarium until you reached certain moments of the story. My passive aggressive responsive was to do a lot of experience farming, and then be able to unlock a bunch of abilities when the next part of the crystarium unlocked. Sweet vengeance. You're not my mother, FFXIII!
I do think under-levelled and on-level runs in games are really satisfying, but I have a deep integral need to be over-levelled when it comes to FF games. Maybe it's relaxing monotony? I don't know. The level design is generally quite enjoyable, too, unlike P3/P4, so I'm not trying to get out of the areas as quick as possible. (Thank god for P5.)