Does JavaScriptSerializer's MaxJsonLength limit apply to string content within objects or just JSON structure?

//1st way
public string GetSomeData()
{
    List<SomeObject> largeCollection = GetLargeDataCollection();
    
    JavaScriptSerializer serializer = new JavaScriptSerializer();
    json = serializer.Serialize(largeCollection); // FAILS - MaxJsonLength exceeded OK
    return json;
}


//2nd way
public string GetData()
{    
    List<Data> resData = GetLargeDataCollection();
    
    // Pre-serialize with Newtonsoft (creates ~10MB JSON string)
    json = JsonConvert.SerializeObject(resData); 
    return json;
}

[HttpGet]
public JsonResult GetUsers()
{
        var Data = GetData(); // 10MB string
        
        // This works fine even though MVC's Json() has ~100KB limit
        return Json(new { 
            data = Data,        // 10MB pre-serialized JSON string            
        }, JsonRequestBehavior.AllowGet);
}

When JavaScriptSerializer serializes { data: "10MB string"}, does it treats the pre-serialized JSON string as a simple string value and doesn't count the string's content toward the MaxJsonLength limit - only the JSON structural overhead (property names, brackets, etc.) is counted? Otherwise I don't understand why it is not breaking!?