Most papers are meh
Academic research is about producing meh to dampen the enthusiasm of bloggers for insight porn
The result of most research is “it is complicated and depends on various factors in unhelpfully nuanced ways”
ie, meh.
Meh is the mediocre folk concept version of your idea of mediocrity. The distinction is just that they started to say "mediocre" but got bored, decided that was good enough, and trailed off...