You are welcome to your belief. The application of craftsmanship can be art.
The application of anything can be art, if it's applied to the act of making art. Otherwise, however, it's not art. It's just another tool an artist can use, or not use, to make art with. Illustration is not art. It's a craft, like metal casting, or stone carving.
Of course pavement art from the Renaissance period has washed away and you would have difficulty hanging it on a wall for you to stand and ponder the deeper meaning of the artist.
Impermanence is also an idea that an artist can use, or not use, to convey their experience of being, to others. But again, the tools and materials and processes used to create a work of art are not what defines the result as being art. Until you understand this, you understand nothing about art.
But if the artist considers it art and those viewing the work consider it is art and the name of the "craft" considers it art and Banksy considers it art and the definition of "performance art" considers it art then perhaps you would see value in re-evaluating your bias.
I don't need other people to tell me what they think it is because I already know what art is and what it's not. Art has a specific function and purpose in the world. If the purported "artwork" fulfills that function and purpose, it's art (maybe it's good art, maybe it's bad art, but it's art). If it doesn't, then it's not. What people who don't know what art is, call art, is of no consequence to me.