Does the book follow on from this to consider whether desensitisation would ultimately lead to the opposite effect?

Why wouldn't people document all that kayaking and island explorations and so on online?

I dunno whether this sounds unintentionally hilarious (the author's arguments are so weak that they aren't even able to convince their main character, let alone the reader) or like an intentional stab at a downbeat ending which falls flat. Either way, I'm glad you bothered to read the book so we don't have to. Wow.

If Eggers can't grasp the whole "user-generated content" thing it makes him sound like a creaky, out-of-touch crank who doesn't actually have a clue about what he's ranting about, he just knows that he's sick of hearing about hashtags and wants to gripe about it.

vapid trend-chasing on twitter or Facebook or reddit for retweets and likes and karma

It’s a very minor point, but what you write about the picts sounds as if it were all right to have savages maddened by strong drinks if they were real Picts but unacceptable if they were American Indians…

( You could write interesting stories about a barbarian usurper who is persuaded he’s ruling his new subjects for their own good. Howard didn’t. )

He is a coward and lacks any personal quality - he derived his power from digging up a Magic Gimmick and knowing how to use it, whereas Conan and Ascalante became what they are by their own resources and strength of character.

In order to understand what the character represents, we need to turn to Howard’s poetry

she engages in political clicktivism by signing endless petitions or sending "smiles" and "frowns" to various organisations and alternately feels pride at having "done something" and panic at the risk of reprisal from dangerous terrorist groups she has "frowned" at.

That's stretching things just a teensy bit for examples of American vs. English attitudes to the occult, don't you think?

How many real-life friendships and romantic relationships these days have started out online? Are those necessarily less valid than those that began in person?

Also, with respect to this weird Manichean division between fake online experiences and real offline experiences, isn't one of the major things about social media these days the way that the lines between the two are being blurred?

"What if we all behaved as if we were being watched? It would lead to a more moral way of life. Who would do something unethical or immoral or illegal if they were being watched? [...] We would finally be compelled to be our best selves. And I think people would be relieved. There would be this global sigh of relief. Finally, finally, we can be good. In a world where bad choices are no longer an option, we have no choice but to be good. Can you imagine?"

Firstly, the novel fares much better when critiquing or satirising The Circle than it does when trying to present a positive contrast or alternative to it.

"The tools you guys create actually manufacture unnaturally extreme social needs."

"You willingly become utterly socially autistic. You no longer pick up on basic human communication cues."

"You and your ilk will live, willingly, joyfully, under constant surveillance, watching each other always, commenting on each other, voting and liking and disliking each other, smiling and frowning, and otherwise doing nothing much else."

Either story should eventually result in her turning against The Circle, but in fact Mae ends up siding with it, rendering Kalden's climactic authorial insert even more undramatic as he doesn't even manage to persuade her.

The novel is effectively forced into an inadequate account of these matters by the way in which it conflates the roles of social media companies and social media content providers: as an employee of The Circle, Mae is avidly followed by huge numbers of social media users and part of her work for The Circle is to provide content for them - yet of course, in reality the social media platforms themselves do not produce most of the content that appears on those platforms.