Another example: It's frustrating that Flax had to implement it's own "lifted" transformations instead of being able to just use jax transformations -- which makes it impossible to just slot a Flax model into a jax library that integrates ODEs. Equinox might be better on this front, but that means that all the models now need to be re-implemented in Equinox. The fragmentation and churn in the Python ecosystem is outrageous -- the only reason it doesn't collapse under its own weight is how much funding and manpower ML stakeholders are able to pour into the ecosystem.

Given how much the ecosystem depends on that sponsored effort, the popular frameworks will likely prioritize ML applications, and corollary use cases will be second class citizens in case of design tradeoffs. Eg: framework overheads matter less when one is trying to use large NN models -vs- when one is trying to use small models, or other parametric approaches.