Is there anything technically lacking from Blender that was used in these Maya/Arnold renders, based on volume displacement? I believe it's a camera based projection for the distortion for the most part.
Displacement — Blender Manual
Use Volume Displacement to Create Celestial Renders | Greyscalegorilla - YouTube
Is this already volume displacement ? : r/blender
Volume Displacement Shader - possible for new 2.79 Principled volume shader? - Blender and CG Discussions - Blender Artists Community