When I joined Mastodon, this article really helped me to understand some of its history, and some of the feelings of people who've been here longer: https://medium.com/@alliethehart/gameingers-are-dead-and-so-is-mastodon-705b535ed616
It starts out gloomy and has talk about Mastodon dying and such, but it is really a great analysis of how community and development of a network like Mastodon are intertwined, and how things can go wrong.