And the reality too is that many of the wild relatives just don't live as long as those pets that get all the extra attention and care. A feral cat has a much shorter life span than the spoiled rotten things we are slaves to.

And I doubt there are any wild horses out there that live to be 35, as my Honey did.
Honey had her vaccinations to keep her healthy, wormers to keep her cleaned out, fly sprays to make life tolerable, and when she had no teeth and started having disgestive problems, there was a vet available who was happy to hook up those IV-fluids (at a price).
My sister once asked how wild horses keep their hooves trimmed, and I explained that rough terrain does the trimming (like natural perches for our birds), and when they have a real problem and become lame, they become part of the food chain, whereas our tamed horses have a farrier to keep them trimmed and stalls for those times they might become lame.
So natural isn't always wonderful, either.