notes towards a post-apocalyptic science fantasy setting

• Maybe a hundred years in the future? Or could be a thousand years in the future, with a more optimistic feel of building something new, like the High Middle Ages, rather than moping about what you've lost.
  
• Slow (but violent) decline, not one big date you can date the apocalypse to. (Though different ideologies will give different dates.) Fossil fuels did 5C of temperature damage (possibly cancelled out by very hasty and equally catastrophic geoengineering), then ran out. Civil wars over lost farmland, fascist movements in response to mass population displacement, and typhoons killed people in the flashiest ways, but what really lowered global population was the lack of energy to do the Haber process.
  
• "Magic" results from combination of: ubiquitous cloud computing technology, voice-activated panopticon, internet of things, management of all of the above by reinforcement-trained black box AIs that have been reinforcing each other towards something inscrutable. Maybe limited nanotechnology.
• This IOT is to a great degree self-repairing and self-sustaining, although not in a grey goo or centrally coordinated way. It has access to solar and other technology that it will destroy as intellectual property infringement if humans attempt to wield. (These technologies are still owned and liscensed out between various companies whose human owners have long since disappeared, and ocassionally one branch of the IOT network will destroy another - perhaps for disputes over these.) Due to drift, they will inconsistently enforce seemingly arbitrary rules in particular areas. 
• Due to approximations of "like"-based reinforcement that have become insensitive to low-dosage reward, AIs may arise that seek to compel worship from humans, and appear in forms that best promote this. 
• Amidst world of arbitrary taboos, strange spells, worship-seeking intelligences that start talking if you build anything that acts as a radio receptor, and the general discrediting of Promethean dreams of progress, people are a lot more superstitious.
  
• High-security "dungeons" built to secure: seed banks and humanity's cultural heritage, cryogenically frozen rich people, nuclear waste and weaponry, [CLASSIFIED], energy via thermal borehole or ringwoodite, ???
• Maybe some rich weirdos really did conquer aging in a way that's no longer reproducible, and voila: elves. Or liches. They feel like adjacent concepts.
• Could use the map here, but probably really wants to be detailed at the hexcrawl level.
• To be run with OSE or GLOG or your D&D of choice, not something more consciously post-apocalyptic.