Orson Scott Card saw this coming last century and wrote of a character who maintained 2 online personas who became the thought leaders of opposing groups.

Some of the late gen-x/millennials who saw this coming may have been inspired to read Endor's Game after seeing the movie

Even earlier than that. "Pseudonymity" (not using your real name online) were adopted very early on Internet. Facebook is the big exception.

This first claim seems weak to me, and the arguments made in TFA are generally weak IMO. It feels that this theory tries to "eat more than it can chew"; they try to explain a lot of things with a single hypothesis, which in the end yields unconvincing explanations.

For instance, let me answer the 4 opening questions:

Why is the news media so interested in telling you how much the world sucks all the time?

Because fear sells; but that aside, one can also say that we are a species who loves solving problems, and pointing them is generally the first step to a solution.

Why are so many of us obsessed with distraction and managing our attention?

Because something is aggressively trying to steal attention - that is, actually, time - from us. It's self-defence at this point.

Why is it so hard to stop comparing ourselves to others?

Because of the atavistic instinct of reproduction, in which mating partners are selected mainly based on social status. It takes training to go against this instinct, and it is even more difficult when your time is being stolen.

And why does everything in art and design seem the same these days?

That's something a boomer could say... Mainstream designs can, maybe, look similar because when you target a large market you design for the average taste. Non-mainstream designs are just more expensive, harder to find, and less visible.

I think this is one reason online anonymity is so important for some of us. It is the thing that let's us tamp down the great unification, at least a little.

If you keep them distinct unification is a weapon to be used against you. You're writing your own blackmail someone just has to call you on it.

With prose fingerprinting, sophisticated tracking, now your identities are only separate by rapidly eroding social convention. Intentionally merging them allows you to have control over the process, and helps you maintain discipline about what you reveal where. If you don't do it it will be done to you.

The article explains the distinction between identity and character. You are talking about character.

I'm not a neurotypical xenial, but I wasn't any good at compartmentalizing, or when I tried maintaining different identities it didn't feel honest, like I was pretending. I didn't like the thought of anyone ever seeing sides of me that were inconsistent with each other.

Unfortunately that isn't a solution. When you keep separate identities, the only thing that can exist across platforms is your own participation. Everything you say and do is isolated to whichever identity and platform you are using in that moment. You still don't have the opportunity to exist completely, because your self has been fragmented. Even if you did manage to create a cross-platform identity, the product of your participation is fragmented, and every story you tell is objective to that platform's context. Even if you tell a story that links across platforms, you are still isolated to that specific cross-platform context.