When an art critic turns up their nose and says “It’s been done before.” you can ignore anything else they say because that person isn’t thinking clearly.
To be creative you have to remember something you learned in the past and combine it with something else. Then you have something new.
I didn’t invent embroidering mirrors on fabric. I didn’t invent using wire and innerfacing to make fabric hold a shape. I only had to find things I like and put them together, then ask “ok, What is this thing I made?” And people think I’m creative but I never invented anything in my life. This is why it’s important to learn from the masters if you want to be a great artist. They can teach you what works. Then you get better results because you have knowledge and experience to draw from.