"the artistic equivalent of breaking into the Louvre and painting a moustache on the Mona Lisa

A fallacious analogy. In no way is the original song affected. A more accurate analog would be someone buying a poster of the Mona Lisa and painting a moustache on it, or using it in a collage Which is the kind of thing that has happened often enough - for example. Meanwhile the original Mona Lisa is still up on the wall in the Louvre, and available on the Internet, for all to see.

I was pleased to see George's readiness to accept changes and variations to his own songs, and in no way surprised. Good songs are resilient, and don't need to be treated as if they'll fall to pieces if they don't get handled ultra-carefully.