SBF said-
Life is not always preferable to death. We all know this, that's the problem. Who gets to decide in each case? I think the individual's autonomy with respect to their body and their life should be respected.
SBF, the hairy horsefly in the ointment with such libertarian approaches is that many people DO suffer from mental and physical conditions that lead them to make choices they wouldn't otherwise make, eg diabetics are known to make irrational decisions when their blood sugar gets out of control (and similarly their mentation becomes clouded, but returns to "normal" once their blood sugar is stabilized). Many people suffer from depression which after it's managed say, "Wow, thanks: I didn't know what I was thinking, as I wanted to kill myself!" The elderly suffer from dementia/Alzheimers, which also obviously effects their decision-making skills, and they need someone (hopefully a family member) to make healthcare decisions for them.
The age of 18 is somewhat arbitrary, yes, in that we have to draw an arbitrary line SOMEWHERE. But regardless of age (whether 19, 49, or 79), a person may lose the right to self-determination to make such informed decisions over their healthcare if there's compelling evidence indicating they are not of "sound mind and body", since they might lack the ABILITY to make sound decisions. Although guidelines exist, it's a judgment call, and that's what this judge did: he made a judgment.
Humans are dependent on the condition of their brain being in relative healthy condition, and having been raised in an environment to give them the ability to make sound decisions. A group like the JWs presents intentionally-biased information, and uses social coercion in order to compel members to make a certain decision, backed by the belief in the religious threat of eternal judgment and damnation by Jehovah (where religious beliefs in adults are protected by 'freedom of worship'). Adults are able to consent to that belief, but minors are not. As Richard Dawkins says, it is completely inappropriate to refer to 'Catholic children' or 'JW child', since children are not able to make any other decision that is legally-binding (eg to enter into an inforceable legal contract), so why should they be described as having chosen a religion?
(IMO, baptisms of minors are eyebrow-raisers, since it's a life-altering decision which although currently legal, probably shouldn't be.)
You objected earlier to the title of the thread, complaining that it's not about the right to die, but it actually IS: if the minor refuses treatment, it would be tantamount to choosing death. You're trying to create a "distinction without a difference", since the end result would be the same: the minor was much more likely to die if he had been allowed to refuse blood, since Hodgkin's lymphoma is one of the more-easily treatable cancers, with vastly-improved rates of survival between those who are treated vs those who refuse treatment.
But anyone who thinks there's a simple "one size fits all" answer here is fooling themselves, and are likely blissfully unaware of the many variables and issues that exist.
Adam