Might've been a change in the past 2 years or so but I feel like completion percentages used to be way lower?
For example, I've seen completion achievements that take ~20-23 hours to beat like Hammerwatch 2 "Dark Citadel – Beat the Dark Citadel" achievement at 37%! That's a HUGE percentage considering the playtime it takes.
In comparison, 10% of players of Hardspace: Shipbreaker finished career mode (that takes about 27 hours according to how long to beat)
On the other hand 23% have the 50 hours achievement of getting a rocket to space in factorio (maybe a bad example as that got a little bit easier with the dlc update).
Posted by throwawayaccount442