I'm with you, I've been preaching quality of life to them for the past few years now but I've been told in no uncertain terms that I'd better watch out or they'll use the same standard on me when I get old
In their defense that darn cat always pulls through, he's putting weight on again, he's jumping up and down off the couch , he's no longer hiding and very sociable again, and he's back to eating kibble and canned as well as what he gets through the tube. It turns out he just pulled the tube out a a couple of days ago and the vet said leave it out, he can put it back easily enough if they need to.
My own cat is 18 and skin and bones and only weighs 4.2 lbs but she's on thyroid medication and eats anything and everything in sight. Her overall demeanor is feisty and where food is concerned she will kill my puppy who's 3 times her size.
I've had to put down my best ever dog a female German Shepherd in 2018, my other shepherd in 2019 ( Christmas Day) and the moment the cat shows any sign of pain, I'll take her to be euthanized but so far she's doing okay.