Edit-Well.. yeah, a bigger engine versus a smaller at the same output is a given. What about the same sized engine at different levels of torque versus speed?
Intuitively, given two identical engines - the one spinning faster would wear out first. I say intuitively as this can be seen in generators - fast spinning emergency generators (operating near 3600 rpm) aren't expected to go beyond 500 hours of use whereas long term utility generators (circa 1800rpm) can go well beyond that. I guess the same can be said for marine engines too.
Not sure if that answers the question -- but keep in mind I'm sharing anecdotal information, I don't claim to be an engine life expert
Another interesting tidbit of information would be the life expectancy of a motor cycle engine - one that lives in a high rev range. I'm curious what, if anything, is done to those engines to keep them reliable.
Time is the best teacher. Unfortunately it kills all its students.