One book I'd recommend that hasn't been mentioned in the other answers is Toby Ord's The Precipice. It focuses on existential risk more broadly, rather than just on collapse, but several parts of the book are about civilizational collapse, or are quite useful for thinking about that topic.
I've also previously made "collection of sources that seem very relevant to the topic of civilizational collapse and/or recovery". You (or others) might find that collection helpful. It includes books as well as other types of sources.
I definitely think this is a very important topic, and I'm glad to see EAs interested in it!
The Collapse of Complex Societies by Joseph Tainter is fantastic. It tries to establish a general theory behind past civilisational collapses. It looks at economic factors which lead societies into decline and argues that diminishing returns are a predictor and cause of collapse.
Collapse: How Societies Choose to Fail or Succeed by Jared Diamond is very good too. It focuses on case studies of societies which have collapsed for ecological reasons.
Thanks! :)