Now the legacy Edge will no more receive security updates. If anyone still using it then they should start the process of switching to something else.
Microsoft Kills Support for the Old Non-Chromium Edge
Originally, the Legacy Edge codenamed was “Spartan” and was included with Windows 10 as the operating system’s default web browser. After that the company officially named it Edge. The Edge was in beta throughout 2019 and officially launched in January 2020. Microsoft has also announced that the Legacy Edge will automatically be removed by the April Windows 10 update, and users will need to install the new Edge. Recommended Reading: Microsoft is Testing Edge Chromium Version for Xbox