I took a course on massively parallel programming taught by one of the authors of this paper that extensively used Futhark and CUDA. While I have not used any of these languages since, I have used JAX[1] quite a lot, where the learnings from this course have been quite helpful. Many people will end up writing code for GPUs through different levels of abstraction, but those who are able to reason about the semantics through functional primitives might have an easier time understanding what's happening under the hood.