But those are all database abstraction mechanisms or ORMs. Regular SQL access to postgres databases is pretty much a fully solved problem in F#, even if the ORMs are not.
Definitely a personal take here, but since I've worked for a while with postgres, a "high-level, production web stack" for me is something that has an established, good DX way to work with this popular database.
Managing ADO.NET connections, working around the type systems and writing a lot of mapping/connecting code are all things that don't solve my business problem.
While not prolific, I've written a handful of production web applications in F# (Suave, Giraffe, Saturn, and Razor Pages) as well as other stacks, and have found a hybrid approach that works for my concerns, but I've found a comprehensive solution not as simple as other ecosystems.
I see questions frequently about data access and serialization/validation in F# web apps, which I had specific sections about. Hopefully I'll have some time in the near future to continue the work.
In the mean time feel free to DM me any questions. There's nothing too fancy about the code. If you looked at other production code, and swapped out what your best guess for the F# translation would be, you're probably most of the way there.