Even more amusing: My wife has an older Dell Precision laptop that, according to Dell's own website (and my own experience trying to upgrade it) cannot be upgraded to Windows 10. Yet, the upgrade icon is in the system tray. I've warned my wife to be aware of this nagware popup and to be careful about accidentally accepting the upgrade.
To Microsoft: Remove your invasive, difficult-if-not-impossible-to-disable telemetry and data-gathering services and you will eliminate perhaps the biggest reason to remain unupgraded. Until then, this nagware screen just throws fuel on the fire.