Here is how one way to do it:
- Open the Command Palette
⌘ P - Search for and select
Properties view: Show all properties - Right-click on the tag and select
Renamein the All Properties view
You are right, the original way shown in the video (left click and type to rename) no longer works.
It seems that the way to rename a tag has changed since then and is now “hidden” behind a right-click menu probably to prevent unfortunate mistakes when using an unintended left click.