Nvidia libs for direct volume rendering of (transparent) isosurface?

My situation:
PhD student developing a free-surface fluid simulation for the GPU.
Looking for a library/framework to visualize the fluid, which effectively means visualizing a transparent isosurface.
The library should be performant and easy to use.
My data: 3D rectangular array, where each cell contains a fluid fraction (floating-point number between 0 and 1). Each time step the fluid fractions are updated.

What does Nvidia offer? I am disappointed of what I currently found:
IndeX
Seems primarily a (paid?) cloud solution. Which makes it difficult to disseminate my project to others (to reproduce the results or extend my simulation)
There’s a plug-in for Paraview, but according to [1908.09662] A comparative evaluation of three volume rendering libraries for the visualization of sheared thermal convection IndeX is slower than other direct volume renderers in Paraview
Small user community
GVDB
GitHub - NVIDIA/gvdb-voxels: Sparse volume compute and rendering on NVIDIA GPUs
Experimental software. And seemingly disabonened after one (of the merely two) developers left
Small user community, little documentation
NanoVDB
Accelerating OpenVDB on GPUs with NanoVDB | NVIDIA Technical Blog
Somewhat between experimental and mature software
Few developers
Small user community, little documentation
“NanoVDB grid is a read-only data structure” according to the documentation. Does this mean I cannot update the data values each time step? If so, it’s useless for fluid dynamics
Nvidia Flow
Again experimental software, and disabandoned
Optix
Only supports surface rendering, not volume rendering

It’s 2022. Does/When will Nvidia have a performant and easy-to-use library for direct volume rendering?