The rationale of "declining usage" could be a bit misleading. Two thought processes: 1) Tab groups are disabled by default on clean profiles (you have to move

The rationale of "declining usage" could be a bit misleading. Two thought processes: 1) Tab groups are disabled by default on clean profiles (you have to move it out of the 'customise' menu), so tab groups are used by more advanced users, and more advanced users are more likely to be disabling telemetry. Combined, any usage statistics are pretty meaningless. 2) Hiding functionality by default will mean it gets used less. Showing functionality by default (Hello, Pocket) will mean it gets used more.