SharePoint Server 2019 has an updated telemetry management experience.
When you first set up a farm or browse to the SharePoint privacy settings page in Central Administration, you can now provide an email address for the telemetry contact of your organization. This is in anticipation of future telemetry reporting capabilities
that will allow customers to associate SharePoint Server and OneDrive Sync Client telemetry with their hybrid tenancy.
The email address provided is not sent outside of the SharePoint farm, not even to Microsoft. It is used in combination with other farm data to generate a unique hash value to represent your farm when uploading telemetry data to Microsoft. When customers
want to associate telemetry with their hybrid tenancy, this email address will be part of the process to prove ownership of the telemetry data.
Customers can opt in and opt out of the telemetry experience at any time.
To configure privacy settings, go to Central Administration-> System Settings -> Farm Management-> Configure privacy options.

New and improved features in SharePoint server 2019.
https://docs.microsoft.com/en-us/sharepoint/what-s-new/new-and-improved-features-in-sharepoint-server-2019
Deprecated or removed from SharePoint 2019.
https://docs.microsoft.com/en-us/sharepoint/what-s-new/what-s-deprecated-or-removed-from-sharepoint-server-2019
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