Really interesting post. As I read it I was wondering if you had read Goffman, "The Presentation of Self?" He talks about how we present ourselves in different social contexts. We present ourselves differently at work, than at home and with family. The internet has definitely aggravated divergent representations of self, but a case could be made it’s not new phenomena. One thing I think has really taken off in a way that wasn't present before is personal branding. Given the nature of the economy, we all are told we need a brand. However, the rate at which opportunities emerge and disappear means these brands are highly unstable. For me this is one of the most alienating elements of how we live today. I find myself often crafting identities that in truth have no value or meaning to me whatsoever. I think you've definitely hit on my Social Media is regarded as the new smoking in terms of health impacts.
https://theroamingmind.com/2017/03/06/social-media-is-the-new-smoking/

Pretending to be others and engaging with others we know are presenting only a particular form of themselves deliberately is exhausting and creates a deep sense of "placelessness."