The linked pdf explains the main differences (in the abstract at the start, you don’t have to dig into the technical details, but you can if you want more info):
However, existing compressed read-only file systems use fixedsized input compression, which causes significant I/O amplification and unnecessary computation. They also consume excessive runtime memory during decompression and deteriorate the performance when the runtime memory is scarce. In this paper, we describe EROFS1, a new compression-friendly read-only file system that leverages fixed-sized output compression and memory-efficient decompression to achieve
high performance with little extra memory overhead.