that's exactly what 40k is though. it's not for everyone.
the term grimdark was popularized by 40k's tagline "In the grim darkness of the far future there is only war." it refers to a subgenre of fiction with a tone, style, or setting that is particularly dystopian, amoral, and violent. very, very few fictional universes approach 40k in the shit scale for the average citizen. badly written 40k even ends up getting called grimderp wherein the suffering is toned up to 11 for edginess’s sake or is just plain stupid like "millions and billions of guardsmen dying per SECOND". this game however is just the correct amount of grimdark which is why most of the 40k fans here like it. this isn't even the WORST example of an imperial world.