Fair comment. But I must admit that I use the pump sooo rarely, and it is always kept in good nick. As the problem you mention is all about the hose connector, I'd probably carry a spare hose rather than the whole spare pump. It's possible to go overboard with spares and where do you draw the line?
Spare chain? Spare saddle? Spare rim? Spare handlebar? I have heard of all of these failing for someone on a tour at some stage
Note: I do not carry any of these as spares, nor do I ever plan to.
I use a pump rarely myself. But like I said, these Lezyne mini-pumps are very lightweight at 90g each and also very compact, and I HAVE had one fail on me. It wasn't the o-rings in the tube, BTW, but rather in the pump part. This happened in bitterly cold weather, and fixing the pump would have been difficult, since my hands would have become numb but fixing those o-rings requires a delicate touch. I didn't actually NEED the pump at this time, I was just topping up my tires that had gotten a little low in pressure, but it was a wakeup call. Flat tires can occur at any time and you can't fix them without a working pump. The Schwalbe Mondial is NOT immune to nails sticking straight up.
Not planning for a broken chain is unwise. Broken chains are not uncommon, though I've never had one myself. The SRAM PC830 that I use is a good chain, but there are always manufacturing defects. I carry 5" of spare chain (5 full-links) plus 3 spare master links.
A broken saddle or seat post just means you have to push the bike out to the nearest highway or town. No big deal.
Rims usually crack before they completely disintegrate, so it would be wise to examine them frequently and I do. If a crack is found, you should be able to make it back to a highway or town before the cracks gets too big. Just be gentle and perhaps push rather than ride to take some weight off the wheels. A friend of mine had his rim crack while desert touring. He was able to continue riding on it to town.
The main problem with a broken handlebar is that you can no longer push. However, it is possible to improvise. I carry a hiking stick as part of my gear (self-defense from dogs, front support for my tarp, self-defense from mountain lions when hiking) and that could be used to steer the bike while pushing. Another possibility is the seat post. Long stems can also break, but mine is short (70mm) and so very unlikely to break.
A broken handlebar might cause a crash which breaks your wrist. If this happens in cold, raining and windy conditions, then you'll need shelter fast to avoid hypothermia. Can you pitch your shelter one-handed? It's simple to take one-handed setup into consideration when choosing a shelter, and usually doesn't add weight.
If you travel in the desert, are you prepared for leaks in water bottles/bladders? Leaks are possible even with high-quality containers, and are easy to prepare for by simply distributing your water into multiple containers.
I'm not a fanatic about survivalism, but it is seems foolish not to be prepared for common contingencies when you are touring at a leisurely pace, and hence weight is not a major concern like it is for racers.