Seems to be about the same as it's ever been.
Still being updated and worked on, and still very few people use it.
It is, hands down, my best experience working in a functional language. I do hobby work in it, and it seems super nice, but I'm not sure where everyone is.
> still very few people use it.
Looking at a chart of GitHub and StackOverflow usage[1], OCaml/F# seem almost steady compared to the other functional languages, my suspicion is that Rust absorbed a lot of programmers looking for functional concepts in programming languages.
[1]: https://tjpalmer.github.io/languish/#y=mean&weights=issues%3...
It’s a great platform, in some ways it’s like a secret weapon…
I joke that F# is kinda “easy-button Rust” lol
The productivity benefits are small and sprinkled - I don't personally think there isn't one "killer feature/app". It isn't just one thing, its little things that add up. Given the team jumped from other ecosystems (e.g. Go/Node/etc) they found F# easier to approach than C#. This is the perspective of the team I run and it comes up in PR comments (I do less code writing these days). Comments like "don't have to do this in F#", or "we need a framework for this because C#" are known to occur. Easier unit test writing, less dep injection headaches, concise function passing, easier inlining of math for perf, easy mocking/stubbing, unions, etc etc.
The big weakness to me is that the people that use it typically don't want to flaunt it, and that means good mentoring, the best/simple patterns to use, etc and management buy-in are not really public. Communities that you can join are not into large scale apps, meaning good scalable patterns and lessons learnt are hard to find.