Dead in the sense of 'put on a bus'. Functionally dead as a character, since they aren't even going to give her the treatement given to centipeetle, where they repeatedly try to give her chances.

Even if they start looking for ways to cure the corrupt gems, Jasper is like… D-list for that. They would first go for centipeetle, then some of the other gem monsters we have seen on airs, then just random gem that are bubbled… then they would try to find a way to help the shattered gems and the cluster… then they would give Bismuth some psychiatric help… then they would fight and defeat yellow diamond… then go to disney land… and maybe some point after that they might fix jasper.

General point- jasper is an enemy combatant that is now a mental patient/giant monster. She is VERY low on the list of priorities. So they are likely not going to fix her any time soon.

wait, some people think she's actually dead?!!