Eh, probably a design decision. They have made many other minor or trivial changes that don't necessarily have an obvious reason.
Nah I don't think it is intended, because there is another NPC called "Kaldani" who is also permanently stuck sitting on a chair.
She is supposed to go to Kanon's corpse and bury him, but she is permanently stuck sitting in front of the campfire so the encounter never plays and Kanon doesn't get buried. Only by moving the chair from underneath her does she do what she is supposed to.
