F# is a big language, it is a ML multi paradigm language that interoperates with C# so there is a lot of necessary complexity and many ways to do the same thing. A strong benefit of this is the ability to create a working functional paradigm prototype that can iteratively be refined to a faster version of itself by hot spot optimizing the slower parts with equivalent highly mutable functions while staying within the same language. Similar how one would use python and C++ and over time replace the python code with C++ code where performance is important.

For the specific case of C# use of await it is unfortunate that C# didn't design this feature with F# interop in mind so it does require extra steps. F# did add the task builder to help with this so the 'await' is replaced with a 'let!' within a task builder block.

  let getById(id:int) : Task<string> = failwith "never"
  let doWork(post:string) : unit = failwith "never"
  let doThing() = task { 
    let! post = getById(42); 
    doWork(post); }

Alternatively the task can be converted to a normal F# async with the Async.AwaitTask function.

  let getPostById1(id:int) : Async<string> = async { return! getById(id) |> Async.AwaitTask }
  let getPostById2(id:int) : Async<string> = getById(id) |> Async.AwaitTask 
  let getPostById3 : int -> Async<string> = getById >> Async.AwaitTask