Used to insult or degrade an opposing opinion, labeling it as average or poor quality.

when you're hungover as shit after a spending a night drunk as a skunk

mid-grade weed

anime watchers who have a superiority complex and believe that every popular show is boring, and instead try to get you to watch unpopular shows that they call peak fiction
e.g.: midruto, mid piece, mid note, mid hero academia, attack on mid, mid slayer, mid art online, midland saga, jojo's mid adventures, mid exorcist, midtail, full mid alchemist, midkyuu, mid clover, bunny mid senpai, dragon mid ball, the promised midland

Basically means average

5/10

mid-grade marijuana

Basically means trash. It's common word in anitwitter that toxic butthurt cry babies would use to describe a popular anime that they think has no character development, a generic storyline, little to no world building etc. Most of the time its the complete opposite.