If you install the new Microsoft Edge (Chromium) manually, you can uninstall it, but that’s not the case when Windows 10 installs it by using Windows Update, in case of latter, uninstall option for Microsoft Edge will be grayed out in the Settings app, but still, you can remove it by using the Command Prompt.
New Microsoft Edge browser based on Chromium on Windows 10 can be installed manually or Windows Update installs it automatically when you don’t do that.
New Microsoft Edge is now being automatically installed on Windows 10, 8, 8.1, and Windows 7 devices.
Microsoft Edge installed by Windows Update will replace Classic Edge and cannot be removed from Settings App or Control Panel’s Programs and Features applet.

We reported once Edge Chromium can’t be uninstalled, that’s now true for Windows 10 devices that got Edge via KB4559309 update in June.
For these devices,
- The Uninstall option for Edge will be grayed out in the Settings App.
- The KB4559309 update won’t have the uninstall option
But you can still remove the new Edge and bring back the legacy Edge or install Edge manually so that Edge won’t be automatically installed next time.
For that,
Uninstall new Microsoft Edge installed by Windows Update in Windows 10
1. Open Command Prompt as administrator
2. Copy and paste the following commands one by one:
C:Program Files (x86)MicrosoftEdgeApplication83.0.478.58Installer
setup.exe --uninstall --system-level --verbose-logging --force-uninstall

3. Now you can access old Edge or install new Edge manually or use blocker toolkit to prevent automatic installation of Chromium Edge through Windows Update. [Via Deskmoder]
Related articles:
New Microsoft Edge now available via Windows Update for Windows 10 1803 to 2004 versions
New Microsoft Edge Stable Kills Old Edge in Windows 10
How to run Legacy and New Microsoft Edge side by Side on Windows 10