I would think that a return to the moon would be of great value. The fact is we put man-made objects up there forty years ago. I would think that it would be important to find out what effect the environment of the moon had on the structure and seals of the lunar module.
Seeing what happened to the materials on the moon is important, but not the most important part. Seeing that we can go to the moon at will is most impressive to others even if we take it as a trivial matter. Of course we can do it whenever we want and we have a very casual attitude about it. Those countries that cannot do it at all see this and forever have that sense of 'Just damn!'.