I have tried both a clean reinstall and downloading it from the Microsoft store and neither gave me the "Show desktop overlay when using media keys" option back. Very annoying to have the media keys overlay back.
There is nothing to clean up in the hosts file either.
We can confirm that you're running the New Desktop Experience on your main account, which is still being tested, and we're afraid this option isn't available there. We recommend checking this thread where you can read more about it and give your feedback.
This is constantly being monitored and discussed by the right folks in order to improve the users' overall experience, and new features and changes are constantly being rolled out based on the feedback provided. You can also Subscribe to it so you can be on top of all the new updates we share about it.
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