> Some of this is natural (though I don't believe healthy) but I think some of this is due to social media where people expect others to be aware of all their major events.

I sometimes do this despite not posting any personal stuff on social media. The reasoning here is pretty simple, I usually don't have a full list of all the stuff that happened in the last few years in mind. When meeting someone I see more often, it's quite easy to think about the last week/month and start with the noteworthy events; whereas, when meeting someone after a few years, not only do I need to think about what happened, but also which of those events might interest the person in question and what level of detail is appropriate