Longevity can be indefinite. But reliability is another story.
I'd say 12-13 years is about right. 15, to push it.
Part of the problem is parts replacement. It's no longer as easy to find parts as dealerships and chain stores clean out old inventory.
It doesn't bother me, so to speak, to replace mechanical wearing items. It's expected. I'm less happy with decaying electrical harnesses (80% of breakdowns are electrically-related). Better to replace than to "repair".
Long life isn't about component replacement, but system replacement (as with an AC system). Do things wholesale, not piece by piece retail.
But I'm livid that a cracked dash is a $700 piece of hard plastic. That the rest of the interior should probably be replaced (high heat), makes me less willing to continue. Lack of rust and excellent paint alleviate that somewhat.
Determine the threshold of pain. Where, and what, really aggravates (so that ruminations on a new vehicle commence).
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