With update KB4580364, released at the end of October 2020, Microsoft has added a new Conference Now feature to Windows 10 to simplify the creation of spontaneous video conferences. Anyone who is annoyed by the icon appearing in the already cluttered notification area can quickly remove it. Open Windows+I, select the Personalisation category and click on the Tray entry in the left-hand column.
Scroll down to the Notifications area, click Enable or Disable System Icons, which is blue, and set the Notify Now switch to Off.