Shader compiling is just a graphical technique. DX12 does it too. Just that, Vulkan is nice enough to tell you a bit about it, and Steam has preemptive compiling, which runs most of the compiling before running the game precisely to reduce stuttering during gameplay. If you recall when The Last of Us remake launched, a lot of people were reporting up to an hour of “Loading” time at the menu before the game was playable on first run, and some were even reporting compiling on every single run of the game just as long. That was a bug with DX12 Shader compiling and it was prominent in both consoles and Windows. It's not a Vulkan thing, nor particular about Linux. That is just how graphically intensive games are made nowadays.