My opinion about these two things is that smart work works with the mind to use with little effort. While hard work works to use more time and extra effort for the same results. But in the modern era where internet is increasingly used for all activities I agree to work smarter in order to use a more productive time.
Yes its true, for me being hardworker is good, that is also being sincere and commited to things you are requested to do. However being a smart worker is being wise like you have to find ways to make your work faster and easier to do. Both attitudes are good values to aquire when you are employed. So be a hardworker at the same time a smart worker.