Registering new device with Xcode's "Automatically manage signing"

Does it require Admin role to register the device?

According to Developer Account Help > Register devices > Register a single device, you must be either Account Holder or Admin.

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—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"

Thanks Eskimo!
I also verified it by trying it with a non Admin and non Account holder account and I got an error.

After doing some additional checks it turns out that both App Manager and Developer roles can register UDID if they have access to Certificates, Identifiers & Profiles.

Role Permissions list under the Search for "Add UDIDs" item
https://help.apple.com/app-store-connect/#/deve5f9a89d7

IMHO, that's a shame because it basically means that there is no control over the devices added to the account since Developers are responsible for adding their own devices.