I want to know if there was an update that prevents the client from deleting non part objects or if this behavior only appears in studio and shouldn’t be expected ingame.
Are objects in the character safe from exploiters now?
I believe this will work the same in game; when I tested it out myself, it was only the parts of the character that were affected. I also tried adding a local part, which (obviously) wasn’t replicated.
Does this mean that if I give NetworkOwnership of a part in Workspace, for example, the client can change the part and the changes will be replicated to the server?
The physics, yes. When you push around an unanchored part, you’re close to it obviously, so it replicates to everyone else because you become the network owner of that part.
I believe it uses something like .ChildRemoved so it would only replicate if a child of the Character’s Model was deleted. Children of the character’s children will probably not replicate.
They can. This was reported as an issue some time ago and it still has gone unsolved. For games that have, for example, values directly in the character to emulate health, those can be deleted to simulate invulnerability to damage. Don’t put game-critical values in the character.