I had never heard of that until now. The product description says it's for iPhone 12 &13. I wonder if there is not enough metal in the back of a Pixel 6 for the magnet to hold onto?
Anker Magnetic Phone Grip (MagGo), 610 Magnetic Phone Ring Holder, Adjustable Kickstand, Only for iPhone 13, 12 / 12 Pro / 12 Pro Max / 12 Mini (Interstellar Gray)