EDIT: serious question; would Slack be professional networking or, how does that work under this bill? It's DMing for business, but it isn't really networking.
Nothing in the law restricts to DMs being between two people, it just distinguishes them from public content.
> (I) shared between the sender and the recipient; 171 (II) only visible to the sender and the recipient; and 172 (III) are not posted publicly;
maybe sender and recipient can be considered a group chat with multiple recipients? Otherwise you wouldn't classify something like Kik or Discord as social media.