To start with, 25.809 people have received any merits at all.
That would mean that, all the rest of currently active posters have earned 0 merits per day (and per post), leaving the vast majority out from being able to post. There are also plenty of people who post sporadically and/or in boards that are not showered with merits, and who may well be decent content generators when they post.
But do those 26k people have reached the 200 posts limit? Seems normal to me that a newbie with 5 posts might not have received any merit?
Vast majority of users are probably not even active. But if you make the same calculation with a merit/post ratio I doubt you'll find 90% of user under a 0.005 limit.