That's not quite right. People are just unaware of the power of what they share and usually react quite negatively if their data is used against them and start shielding themselves from surveillance of the sort that might affect them.
So predicting "people won't care about privacy because they share their whole lives online more and more" is a bit disingenuous.
It's what the tech companies like Facebook want but it's far from the truth.
Now I think it will result in unbearable self-consciousness. You will yearn to be offline, quiet, to just forget, maybe to enjoy the moment without it going in your permanent history.
Arguments in relationships are messed up when you can rewind and debate what he said she said. The actual words are often not important, it's the emotions. The permanent record makes it harder to forgive and move on. It's like being in court, everything transcribed.
> given most people with each generation are increasingly becoming more and more comfortable sharing their whole lives online.
There is an entire generation who learned not to post, many who are very anti social media, many who stay anonymous. Chat is much bigger than public social these days.
There are also scenes that avoid digital. They make cassette music and black and white photocopy artwork.
Thinking about it a bit past the initial reaction though, I think it’d actually be a massive boon for relationships. Sometimes we get so hung-up on the wording, that may or not may not have been clearly expressive, but due to some slight subtlety, changed the course of the interaction from a potentially positive one to a toxically negative one. I think if you can just subvert the “you did say that! You don’t remember??/No I didn’t/Yes you did” you can focus on the actual content of the conflict resolution.
I’d personally want to know if I said X-potentially-hurtful-thing. Or was the other person just hearing it? What’s workable, what’s not workable. Post-mortems for arguments (assuming the relationship is a viable one, ie genuinely collaborative & not contingent on point-keeping) would be a lot easier & constructive conversations can be realized much more quickly.