All that command does is remove an app from the machine. If you create a new user on the machine then Windows will simply reinstall the default programs again. Your command doesn't prevent that. To get the list of apps that will be installed when a new user is created run the Get-AppxProvisionedPackage
command instead.
I've never tried it but I believe the Remove-AppxProvisionedPackage command will allow you to remove provisioned apps which will prevent them from being auto-installed.