New member, first post. I was linked to this article from the Yau30 page.
The set-up, or gimmick, of the article is very good. It's a plausible metaphor for internet addiction (out-of-the-closet normie here, btw *laughing poop emoji*). The best section is the text message exchange. Nothing is more paranoia-inducing than the idea that your loved ones can hear what you're saying but are wildly misinterpreting it. Maybe you could include a second exchange between other subjects using the same format? These mutually intelligible miscommunications are the new literary form your SCP opens up.
Addenda B and D don't do much. It's no surprise that the software is being spread by some entity for some purpose. And "withdrawal symptoms" is so vague as to not be scary. What is particular to this type of withdrawal that warrants a mention? I'm just imagining sweaty palms, headaches, and depression. Maybe there's some kind of rage associated with cessation, especially because these people are not only addicted, they're getting their whole sense of worth out of the software's lies.
I think you need another twist in this article to make it really good, and that could come out of the hint in Addendum C: If this is really dangerous enough to be Keter-class, it's because people love it. They prefer their addiction to "reality." What happens when thousands or tens of thousands of people attain superhuman levels of happiness and alertness, but they prefer to stay inside their rooms, convinced of false ideas?