This would seem like the kind of question that sounds at first like a single question but causes a number of others to be unpacked. For example, would someone see a difference between simply pulling a plug, ceasing to feed someone, and administering a drug, or would this being politicized be too much of a fear...

A few things come to mind here as certainties for me. To start out, if a society for whatever reason greenlights the concept, definitely don't institutionalize/politicize it. The moment it even becomes a debate in the public sphere, pull the heck out, the concept is lost. I might not have the greatest relationship with life, but the same thoughtpath makes it hard to comprehend being all willy-nilly about it. In such a society, if anything, I'd say it should be by an individual's own breath that the candle is blown out, so to speak. Going by the same literary device, if the individual cannot produce the exhale to do that, shrug your shoulders. I would not put a dog down for this reason. By the same token, everyone should recognize the gravity of all this, which in most cases nobody does.