Isn't the whole point that resuscitation is an incredibly invasive and aggressive procedure and that there are people with disabilities/health conditions for whom it's not necessarily something they might want?
My daughter had to be ventilated as a baby and it was horrible. Her whole body had to be put into essentially muscle paralysis to be able to do it, and the cocktail of sedatives and other drugs she was on was horrific, weaning her off the opiates in particular was awful.
There's a reason it's a last resort and not taken lightly.