I typed the post in a minute and published, so it definitely isn’t the most coherent or well thought out post.
I’m currently using # for commands executed by the root user or sudo.
Currently, I only use sudo if the command depends on one of its features. Like the example above where I execute a command as the www-data user.
My dilemma was whether to use $ sudo or # sudo for those few cases. But based on yours and other comments, it might make sense to use $ sudo for commands executed as root as well.