Well, the generics problem is that you don't have generics. So you just can't define a lot of general-purpose functions in gRPC, and have to make a specific version of them instead. Even something like "query for objects like this and then apply this transform to the results" just can't be done, because there's no way to pass the transformation over the wire, so you have to come up with a datastructure to represent all the transformations that you want to do instead. "Defunctionalizing the continuation" is the technique for doing that, https://www.cis.upenn.edu/~plclub/blog/2020-05-15-Defunction... is an example, but it's a manual process that requires creative effort each time.

> Does google's `any` package help with the generics problem you describe? (Acknowledging that it's obviously clunky)

Not really, because you don't have the type information at compile time. Erased generics are fine in a well-typed language, but just using an any type you can't even do something like: a function that takes two values of the same type.