If you ask me? Mobile/WiFi internet… The way and amount of time we use our phones had changed A LOT since their diffusion. I guess the release of the iPhone changed our idea of what a phone is too
Edit: when I say modern world I’m referring to the last 50 years. So stuff like “the electricity” or “the telephone” doesn’t count.
And it was a feature added later when they wanted to compete with Twitter. Prior to that, no home feed. Just profile pages, a la MySpace. And it was glorious! It was so much fun to leave wall messages to friends, and see whatever others have posted in them too.
When the newsfeed came about, I remember thinking “I don’t like it. It’s stupid!” mainly because I knew it was a reaction to Twitter. Of course, I got used to it eventually.
But yup. Facebook back then was a neat tool. Not the cesspool that’s been for the past 10 years.