You were being offered a slightly simplified example, the Hue bridge does indeed require authentication.
To answer your other question, the bridge can be accessible via the online “meethue” portal for things like easy remote access but I think this is optional.
EDIT: oh, and it’ll generate internet traffic for firmware updates I suppose!
One thing I noticed from your command: No authentication. Looks like any software on any device on the LAN can control the light. Is that really true?