This is true (with the caveat of some interesting edge-cases with npgsql and F#), however the next paragraph in the article mentions "a lack of a high-level, production web stack".

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.