I think this misses the point. As the article points out, people could and would act differently in different contexts: Home, the Church, the Bar. They weren't lacking opportunity to "exist completely".

The whole point of the omni-context is that you are putting yourself in a space where you have to act in a way that is appropriate to all of those places.

I would say things in the Bar that I would not want the reverend, my grandmother or my children to hear - but in the uni-context I have to mediate my speech to what is appropriate to all of those audiences or risk judgement for it.

The uni-context discourages expression. It's like a dystopia where everything you say and do is recorded and can be recalled for judgement at any time. And yet people sign up for it.

Trying to maintain separate context, different identities across platforms is an attempt to fight against that and to limit the risk that something I say on one plaform is not going to destroy my social credit in every other platform where I participate.