Yeah, much of these (or variations) applied to online live chat or async forums in the '90s. Though different venues had different conventions.
And rules like in the article would all be easy to remember. What's not in the article is whether/what skills you'll need to develop to process all this information and noise.
For example, I remember seeing a busy chat room for the first time in the mid-'90s, and there was so much people talking, and it was scrolling seemingly too fast to read. (Bonus: I was on a then-vintage green CRT terminal, HP 2392A, at that moment, so incomprehensible scrolling of symbols was not entirely unlike the Matrix visual.)
But after some experience with the chat, it was no longer overwhelming. I could glance at the scrollage and have a sense of who was talking, what was being discussed, and possibly some meta of what was going on. And, for incoming messages, I could be tracking and selectively focusing among the often multiple concurrent threads of conversation.
I suppose skills a bit analogous to that might include how to manage the many different online services today you have to be on today, applying critical processing to advertising/engagement feed algorithms, juggling all this inefficient stuff with more real-life things, etc.