Complex sentence: In 1985, the MSX2 was released, which systems often (but not always) included a built-in 3.5 disk drive too, and consequently the popular media for games and other software shifted to floppy disks.
Split into simpler sentences: In 1985, the MSX2 was released, and these systems often (but not always) included a built-in 3.5 disk drive too. Consequently the popular media for games and other software shifted to floppy disks.