We use the bulk admin app and don't have a problem with it. It does not allow project admins to actually update other project admins.
What I would like to comment on is the other request to allow all users to VIEW project admins so they can request access without having to go to a workspace or sub admin to figure out who the project admins are so they can go ask that person to grant them permissions. Is that possible? Is it being considered? It is a huge time suck just trying to let people know who the admin is so they can request access to a project space.