I think Bitcoin first started popping up on social media like around 2011-12. That’s when it began gaining some real traction online, especially after hitting $1 in early 2011 and then skyrocketing later that year. People started talking about it more, and Facebook was one of the places where early adopters and curious folks began sharing info and memes about it. Before that, Bitcoin was mostly a niche thing discussed on forums like Bitcointalk.org and Reddit.
If you’re curious about Bitcoin’s early days, check out this timeline from CoinDesk: https://www.coindesk.com/learn/bitcoin-101/bitcoin-history. It’s a solid resource for understanding how it all unfolded.