While available in many sizes, the presence of a Type I (pins on the short sides) TSOP is a clear indicator of a flash chip in a typical embedded system.
Is there a technical reason for the manufacturers to use Type I over Type II (pins on the long sides), or it is just that they are making compatible versions of the first available chips?
Why is it different for SDRAM, which generally has pins on the long side?
UPDATE: I clarified that I am asking about the preference of Type I TSOP over Type II TSOP. Added SDRAM reference.