> There are Microsoft-backed F# bindings for Spark and Torch > this is despite a pretty compelling proposition of lightweight syntax, strong typing, script-ability and great performance.

For exactly the reasons your mentioned, i feel like F# would have been the perfect match for both MLE/ETL(spark pipeline) work and some of the deep learning/graph modelisation such as pytorch. Saddly, even from MSFT, the investment in F# as dried up