[gregfjohnson]

There are bitter and heartstrong arguments on this topic. Brachycephalic breeds with flat faces or short snouts (for example pugs, bulldogs, boxers, Boston terriers) cause anger among some and devotion among others. (We are a three-pug family.) Pugs have an average lifespan of 12 to 15 years, as compared with the overall average dog lifespan of 10 to 13 years. We have also had (and loved) boxers, which have an average lifespan of 10 to 12 years. Boxers seem to be genetically prone to cancer, which is how we lost our most recent boxer.

There's a classic cartoon showing two wolves in the bushes at the edge of a campfire, looking at the leftovers being thrown around by the humans. One says, "Look, what the heck, let's cozy up to these two-legged creatures that seem to have lots of food. What could go wrong?"

Next frame is a picture of an unhappy-looking pug wearing a birthday hat..

[Doxin]

I think the reason take so much offense at e.g. pugs is because they don't need to be bred that way. Where I'm at a law was passed making it illegal to breed dogs with congenital conditions. As a result basically all the pugs you see here have a bit of a snout as do all the boxers. Crucially this didn't change the breeds personality perceptibly, and it only changes the look the tiniest of bit. In trade you get dogs that are visibly happier and have more energy.

A neighbor in particular previously had two french bulldogs with no snout. They'd spend all day panting and snoring. Once they passed away they got new ones, now with snout. They spend all day running and jumping instead.

[Mumps]

If I'm reading your meaning correctly, about lifespans, I think the comparison isn't quite correct?

lifespan seems to be more strongly correlated by size, not squashed-nosed-ness.

Consider chihuahua, shitzu's (and crosses: bichon-shitzu, ...), poodle crosses, heck lagotto (lagotti?). All can live well past 15.

Versus GSPs, great danes, Irish wolfhounds, and so on, coming in closer to say 6-10 years.

I've never really heard argument on lifespan of pugs et al versus other dogs, though. More around (perceived) ugliness/prettiness, and their breathing issues.