Cant access variables inside the DispatchQueue.main.async

The reason it is not printing value as the process inside asyn block is an asynchronous process and it will not make the calling thread wait for it so when you read value you get nothing because the async process didn't complete yet, but in async block if you read value you get it since execution has been completed. You should refactor this function to pass value in a completion block instead of returning value from function.

Beside this you should make API call in a background thread and return result in main thread.

Something like this should work:
https://medium.com/@oleary.audio/simultaneous-asynchronous-calls-in-swift-9c1f5fd3ea32

A part from link:

func query(text: String, completion([Track]) -> Void) {
   let endpoint = "https://www.something.iforget/search"
   let url = URL(string: endpoint)
   var request = URLRequest(url: url)
   request.httpMethod = "GET"
   request.addValue(//whatever header fields are needed, I forget)
   let task = URLSession.shared.dataTask(with: request, completionHandler: {(data, response, error) in
      if let data = data {
         let json = try JSONSerialization.jsonObject(with: data, options: []) as? [String: Any] ?? [:]
         //Here I parse the json into an array of Tracks
         completion([tracks])
      }
   })
   task.resume()
}

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Based on above example your code should look like this:

func createData(request:Crudpb_CreateRequest, completion(TypeOfYourResponse) -> Void) {

   DispatchQueue.global(qos: .background).async { // call API in background thread
        self.response = try! self.client.create(request)

        DispatchQueue.main.sync { // return data in main thread
             completion(self.response)
             print("This is response 1: " + self.response.result) // <-------- This is priting the right response
       }
    }
}

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