That feature was Super Resolution, an option in the Photos app that upscales your photos and images to be a higher resolution. It's not a bad option to have, but in today's world, an image's resolution is rarely ever its main problem relative to things like lighting, noise, and so on. I still feel like Microsoft is totally missing the true potential of Copilot+, and I have some ideas on what the company could do to make it better rather than waste time with relatively uninteresting features.