With the Blender Internal being gone, one of its features is going to be lost with it, without gathering much attention; Voxel Data Rendering, which is highly useful in viewing Medical Image Data. While Voxel Data Node was once proposed for Cycles (https://developer.blender.org/T41179), it was refused since it is not the ideal implementation for a voxel. However, no better implementation appeared.
It doesn’t matter that much if the node is for Eevee or Cycles, in general we want them to share the same nodes and the same design issues with treating volumes as textures still apply.
I think the right solution is to implement a volume object type in Blender, which can then support reading volume data from various file formats.
Thanks for the reply. As far as far as I googled, the gsoc project implements a Volume primitive for Cycles. I think I should just wait for that to be integrated into EEVEE