Same issue here: FluidMill and other demo scenes have water-like fluids with no coloring. Environmental reflection and shadows work but thickness and turbidity colors on the emitter have no effect. This is true if using the supplied demo fluid blueprints and making new ones. (I have both Opaque Texture and Depth Texture enabled in my URP renderer asset.)
Obi Rope and Obi Fluid in the same project, both 7.0.4.
Obi Rope and Obi Fluid in the same project, both 7.0.4.