Life is not yours to end.
Nor is it yours to keep going once the spirit has left the body. I’m not so sure that it is moral to keep a body alive once the mind and soul are gone. In the old days we would not have had the ability.
People make the choice to let a loved one who is without hope (whether in a vegitative state or not) go to the lord everyday and I see nothing wrong with that. If its a medical certainty that the brain is dead and the patient will never think another thought then why keep the body going? The person inside already left and is with the lord.