FTP does indeed predate compress (ca. 1984), but I'm unsure of the penetration of IP at the time. UUCP networking was more common and that really only carried 7-bit US ASCII. (Including quite a lot of gifs, I assure you. :-) ) And, yes, on the fly compression would have killed most workstations at the time. My own experience, though, from the late '80s and '90s, was primarily using FTP to get .tar.Z files.

For failed downloads, memory errors, and so on, a hash in the protocol isn't that helpful. You really do want a whole- filled hash check after the file is written persistently. (TCP's checksum is a performance optimization, although it doesn't work very well with wireless networks.)

P.s. "wools"? Stupid android keyboard.