It's hard to say how many hours on the bottom end as I bought it used but I would say it is on the higher end for the life of a crank. The left side thrust bearings were looking pretty thin as well so it was probably just its time to go. I was still shocked to see the damage as I figured it would just be a slightly leaned piston. I am really thankful it didn't fully grenade.
And before it comes up, I did leakdown test it before tearing it down and it held 6psi for over 30 minutes.