That’s kinda a running theme on Robert E. Howard’s stories - denegerate people living in the ruins of an ancient civilization. The Lemurians we see in the game are no longer the proud, civilized and advanced people they once were. They’re what remains of a civilization ruined in a cataclysm, whose survivors were enslaved, rebelled, enslaved again by another people and left to struggle after a large-scale cataclysm devastated both sides of the war.
Just like the savage, tribal Picts of the Hyborian Age are remnants of a mighty empire of the Thurian Age. The Atlanteans went back to ape-man level before evolving into Cimmerians.
The gold, silks and other bling make a dramatic contrast to the spartan living conditions of the Lemurians in Conan Exiles, hinting at a legacy of wealth and power. It bears similarities to the people of Xuchotl in Red Nails. They lived in palaces of gold and jewels, but were really just two tribes of savages who lived only to kill each other as brutally as possible.