She's right. Covering up pieces of artwork that were painstakingly created over hundreds of hours isn't respectful - although I am absolutely certain the Ninja Knits had only good intentions.
Art is never just a statue or just a painting. It is, by definition, "something that is created with imagination and skill and that is beautiful or that expresses important ideas or feelings".
I bet the artists that created the bronze animals (foundryman Jonathan Campbell, mould maker Marco Wuest and sculptor Brigitte Wuest) have strong feelings about their work.
The animals took just over a year to make and it shows in the results - the statues are beautiful and incredibly detailed.
The knitting probably also would have taken many hours and a lot of creativity and is also art in its own right.
But, just because it had good intentions, that doesn't make it right to cover up one piece of art with another.
Let's leave the yarn bombing off the public artwork and instead use that creativity to brighten up something lacking art.