Can I remove Windows 10 Timeline's nudge to "see more days in timeline"

Following on lincb's answer, you can set the registry key corresponding to that group policy at:

[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\System]
"UploadUserActivities"=dword:00000000

That is, at that path in the registry, add the 32-bit DWORD

UploadUserActivities

and set its value to 0.

On Windows 10 Pro, Enterprise, or Education, you can use Group Policy to disable the option to upload activity, and this seems to dismiss the nudge. Here are the steps:

• Click Start, search for gpedit, and click the top result Group Policy Editor
• Browse to the path Computer Configuration\Administrative Templates\System\OS Policies
• Double-click the Allow upload of User Activities policy
• In the pop-up window, select the Disabled option, then click Apply and OK

The nudge in Task View should then no longer appear.

I found this as part of the instructions in https://pureinfotech.com/disable-timeline-windows-10/.