unity 非同期でFLGが変わるまで待つ

using System;
using System.Threading.Tasks;
using UnityEngine;

public class FlgWait : MonoBehaviour
{

    /// <summary>
    /// ボタンが押された
    /// </summary>
    public void OnClickButton()
    {
        WaitHoge();
    }

    private async Task WaitHoge()
    {
        bool doHoge = true;

        var _ = Task.Run(() =>
        {
            int i = 1;
            while (doHoge)
            {
                try
                {
                    i++;
                    Debug.LogError($"{i}");
                    if (i >= 10000)
                    {
                        doHoge = false;
                    }
                }
                catch (Exception e)
                {
                    Debug.LogWarning("[Server] " + e);
                    throw new Exception("Error");
                }
            }
        });

        Debug.LogError($"Before Wait");
        await _;
        Debug.LogError($"After Wait");

    }
}