From Revolver:

It all started as a joke. The Sword guitarist Kyle Shutt was smoking weed and talking with his bandmates about how absurd it is that every group that plays slow riffs or evokes feelings of dread get labeled “doom,” even if they sound nothing like pioneers of the genre: Black Sabbath, Pentagram Saint Vitus, Cathedral.

“Man, what if we did a heavy metal Pink Floyd cover band, called it Doom Side of the Moon, and did doom versions of Floyd songs!” he quipped.

Great idea and it turned out really good. You can listen to the album on Apple Music.