For me, the biggest issue this solves is the blank canvas paralysis problem. Artists are visual thinkers and need a little nudge in the right (art) direction. This is a great way to fill that blank sheet of paper with something that they can take and run with.
Editing Gaussian Splats is still a pain in the ass in the artist's perspective. Even if you can create a good-enough first try using scanned data or generative AI, you just end up with a rough draft that you cannot polish in any way. Existing mesh-based tools allow you to edit the geometry relatively easily, since they are in a higher level discrete representation rather than just a point cloud data structure.