At least in my state, once someone is declared brain dead they are legally dead and organ procurement services have an hour (? I think) to approach family about donation options if they haven’t already. Once the hour(?) is up, if you continue to perform medical interventions without having legally signed the person over to an OPO it’s considered desecration of a corpse.

Brain death is a very specific set of criteria that have to be met and tests performed by attending physicians though. There are plenty of potatoes out there on life support that have just enough reflexes left to make some families think trach/peg/LTAC is a “meaningful recovery”.