You're missing my point. If a company creates something that is meant for kids (and I mean very specifically for kids), yet everyone enjoys it, then they've really accomplished something.
If a company has created something for kids and it gets a good reaction from their target audience and that's it, well, they accomplished their goal.
The real problem comes when they create something targeted for kids and the kids don't even like it.
Basically, if they've affected their target audience in the way they were aiming for, then their goal has been achieved. It wasn't designed with teens in mind, so for teens to legitimately expect to get enjoyment out of it, well, I dunno what to say except for: why would you expect that? That's like expecting to get a fulfilling read from a children's book.
LU was targeted at a slightly higher age level, and not only that, but it was REALLY good. Therefore, you have scenario one that I just mentioned - everyone liked it, it didn't matter what your age was. This game would be scenario two. Not only was it targeted at a younger audience, but we could see it wasn't going to be as in-depth as LU. Thus, target age equals enjoyment age.
Anyway, isn't this still in beta? I understand that it will mostly be as it is now, but many things could still change from how it is now.