Often used to describe bands like Pantera and Exhorder. With mid-tempo riffs similar to those found in Thrash Metal and a tendency to focus more on groovy syncopation and heaviness than outright speed.
Sorry for the late reply...
...because those labels are run by sketchballs. So stuff on labels like Werwolf, Purity Through Fire, Drakkar, etc. which tend to sign a lot of those bands doesn't show up on Bandcamp unless the band has their own separate page
They were doing that long before being purchased by Epic Games