I wonder what it means for Slang[0]. Presumably the point is that people want to do GPU programming with a more modern language. But now you can just use Rust...
There's library code in rust that manages GPU memory and schedules pipelines and use a slang reflection to ensure memory layouts between rust and shaders match.
Writing shaders is materially different from writing CUDA kernels, at least for now. Shaders are simultaneously higher and lower level, and have a lot of idiosyncrasies as a result of being designed for a specific and limited set of driver/GPU features.
Stuff like descriptor sets, resource registers, dispatch limitations, …
Also shading languages are more user friendly given their features.
Finally NVida already has Slang in production and those folks aren't going to rewrite shader pipelines into Rust.