I was listing specific examples which appealed to your non standard definition of social media, but you've moved the goalposts, and ignored the extra features such as STI services that even typical social media often lack. Anyway, it seems that you have a narrow and non contemporary definition of social media. It is simply any form of mass communication over the internet, including but not limited to email mailing lists, BBS, or even "just chat" because surprise, people use these systems as social media.

Social media | Definition, History, Examples, & Facts | Britannica - https://www.britannica.com/topic/social-media