This is an interesting topic. First of all, I understand where they are coming from. I wouldn't want that to happen to me either, even though I would be dead. However, I also see problems with this kind of law. As stated in the article, it makes your persona something you own and which can be transferred to other parties. This might be in line with the crazy American habit of expanding IP rights and making money of the strangest of things, but I see a moral and a practical objection.

The practical objection is of course that you never know in whose hands "you" end up. They can do things with "you" which you never wanted. I mean, there is absolutely no way you can control this. You are dead, remember? It just does not work the way you would expect it to. (Also, 70 years is way too long. Unless you are someone like J.F. Kennedy or Mark Twain, popular culture has already forgotten about you)

The moral objection is that if you make the persona marketable, you cannot be you. You cannot develop into "you". That would be wrong. A persona is more than just the punchlines or the sweaters. It is "you". Now, lets say that Marin Luther King is licensed (which he is according to the article). If we take this to it's logical extreme, then someone could not copy MLK, because he is licensed, even if that person is really similar to MLK in whatever way you like. It would hamper the personal development of people. They cannot be like MLK, because he is licensed. It is a bit like what Hitler did with Charlie Chaplin's iconic moustache. Nobody in their right mind would sport that moustache. Just like it is licensed. Hampering people in their personal development is morally wrong and I think this will be the logical extreme.

All the yous and "you"s might be a bit confusing, but this is the best I can do...