Picard, as a person at the turn of the 25th Century, was a man at the end of his life whose decisions 15 years earlier caught up with him when he decided to do something about it before he died. That's the message. Picard is a personal story. And a personal story is about who someone is. Not what they are. What Picard is arguably changes at the end of the season, but I think who he is stays the same. Extra meanings can be added, but I think that's the core message.