I agree with part of what you said. The living will would have done no good, since the Schindlers vowed they would have gone to court to force Terri to live in that condition even if she had said (in writing, notarized) that she would rather die.
Keeping the government from legislating against my end of life decision seems to me to be the best course of action.
I heard recently that EVEN if you have a "WILL-TO-LIVE" specifying you WANT food and water and medical care, that in 10% of the states, a DOCTOR or HOSPITAL can overrule you and/or your family and kill you if they feel your quality of life is too low in their opinion.