Sometimes the firmware is optimized for operation though. WD is one of the most advanced companies in this regard. My 4TB Passport drive reports a drive model which is not sold separately but, it's purpose built to run in an enclosure.

My first generation Passport 320GB disk was also has a different firmware for enclosure based operation.

IIRC some WD disks doesn't have SATA ports but USB ports are directly soldered to their drive boards.

WD is an interesting company.