Suppose there are two men, Bob and Rob, whose mental lives are exactly similar. Both are very happy throughout the majority of their lives. There is, however, an important difference between them: Bob lives in the real world, while Rob lives alone in the Matrix, never to discover his predicament. None of Rob's family and friends are real.* His love is directed towards people who don't exist, and his accomplishments are appreciated by no one. No one shares in his joys or comforts him in his times of sorrow. Now, my question is this: would you rather live a life like Bob's or a life like Rob's? If you would rather live a life like Bob's, your choice cannot be based on any subjective difference between Bob and Rob, for they are exactly alike when it comes to their thoughts and feelings. So if you prefer a life like Bob's you want more for yourself than just being happy. What this “more” is is hard to characterize. Personally, I think it involves the notion that sharing one's life with others is intrinsically good, and that sharing one’s life in this way is something which is not desirable for the sake of any effect it has on our subjective well-being. But what primarily interests me here is what the reader has to say.
*I will stipulate that the simulations Rob encounters are not conscious. If one thinks such simulations must be conscious, imagine an equivalent scenario with a Cartesian demon running the show instead.