Often when I launch a game through Steam that “processing Vulkan shaders” window appears and loads for a couple minutes. Sometimes it takes no time, sometimes it takes several minutes. But then, for larger games like Dune Awakening or Outer Worlds 2, the game needs to sit and process shaders for another couple minutes anyway. But for some games, like Enshrouded, I can skip the Vulkan processing with no problems in the game (I do that because the Vulkan processing doesn’t go anywhere). So what is that Vulkan processing for?
Well, you can play the game without it, as others have stated, you should really leave it on. First of all, all of that work needs to happen then later when you’re playing the game, which is just going to lead to a subpar experience with random framerate drops that cannot be explained. From Software’s Elden Ring had a problem at launch with that. Every time a new effect or literally anything in the game was done, you’d wait for half a second and that would sometimes make your game into a slideshow for seemingly no reason. Or the Nier replicant remake wouldn’t play the pre-rendered cutscenes if you didn’t enable it. Most games don’t care, however. But for the sake of stability, my recommendation is to leave it on. It only takes a long time when you boot something up the first time, and with modern games being unoptimised as well, do yourself a favour and leave it on.