I actually wish the unit system was split off into a separate library. I use it occasionally in my data science work, but it feels kind of silly because I don't use pretty much anything else in the library.
The one thing I really like about the Astropy system is that it's built on PEP-593 annotations and Numpy, The former being effectively free and transparent at runtime, and the latter being a nearly universal standard for numerical and scientific computing.
The docs also reminded me of the existence of Pint, which is yet another standalone unit system that I keep forgetting to try. Do you have some kind of comparison document among Astropy, Pint, and Unyt? It would be helpful to have a sense of how Unyt differs from the others, otherwise my default behavior is to go with whatever is the most popular.