Xcode update stuck after updating macOS
It updated successfully, after around 5 hours. I just did nothing, just left it there.
It is painfully slow when it comes to the 'Installing' stage.
Based on the log from console, it does not look like it is spinning empty.
For example, progress from 94.67% to ...
... 94.83% took almost 20 sec
A lot of the pain of updating XCode from the App Store can be avoided by downloading the latest version from the Apple Developer website directly (including beta versions if you are into them). Use this Apple Developer link.
For more information see this Ask Different answer.