Possibly, but you could say that about the rest of the plane
I suspect some of these life limits are to limit liability. If you stick a 5 year life on something, and it kills somebody at 6 years, they cannot possibly sue.
And that would be true even under the US Part 91 regime, where life limits are non-mandatory (unless it's an AD).
Lyco's 12 year crank life limit is one example of this cynical attitude, on which they sidestepped a class action by offering a "free" crank if you send your motor
to Lyco for the 12yr overhaul
