Yes mine does this and many have said theirs do to varying degrees. It almost feels sunken the back glass.
People have checked the display models in store and have said 90% feel the same. The other 10% are smooth. I initially was wound up by it but am learning to live with it as I love the device. I use mine naked so it does affect me. I may at some point take it back to Apple and either get them to swap it out or resit the glass
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