She doesn't understand tech
Somebody might buy a new camera, even if they like the one they have. She thinks you should use one thing forever. As long as it still works. So drop it on the ground, and her logic will work. Just drop everything you want a new one of, then she won’t care.
Why would I buy the new camera like mine if I didn’t like it? I’d be getting a different brand and/or model if that was the case.
Just don’t tell her what you are buying anymore. Then you’ll never have to hear her intelligence.