Visual artist H. R. Giger is gone now, but as long as the Alien franchise exists, his ghost will haunt it. The guy was into some spooky occult stuff. You don't make a book like Giger's Necronomicon and then peaceably surrender to death's cold embrace. You stick around and haunt stuff, starting with your very own museum in Switzerland.
Back when Alien: Covenant was Prometheus 2, however, Ridley Scott seemed intent on going in a new direction, stating publicly that the film wouldn't feature any xenomorphs at all. "The beast is done. Cooked." It's unclear what prompted the subsequent about-face; perhaps Scott realized that Giger's involvement in Prometheus was its saving grace. Say what you want about the directing, script, acting, and characters, that movie is visually dazzling.
Giger's Alien aesthetic (slime, biomechanics, a metallic black and blue palette, smooth appendages, skeletal hinges, womb-like enclosures, oblong passageways, and so on) is an intrinsic part of the franchise, and from the looks of things, Scott and his team have made peace with the Star Beast. Alien: Covenant represents a step in the right direction with regards to honoring Giger's legacy and keeping his ghost happy.