I feel like you're going to need different filesystem concepts to deal with full byte addressable storage. There's a lot of simplifications you can use knowing

I feel like you're going to need different filesystem concepts to deal with full byte addressable storage. There's a lot of simplifications you can use knowing everything is a world of 512 byte/8k blocks. Everything that's a linked list of blocks would suddenly be lists of "start and offset" instead, because you might have a file was fragmented as "1Mb at offset A, 32 bytes at offset B, and 5Mb at offset C". You'd likely need some tradeoffs for minimum fragment sizes to avoid a file sharding into a million 32-byte fragments and requiring a huge number of distinct reads to load, and maximum sizes that would be manageable without overloading the recipient device's buffer.