First note that the question implies that 5.25" 360K disks was the beginning of computer programming and it was not. Before IBM designed the IBM PC, IBM had already designed and implemented many computer systems and operating systems.

Sophisticated communications capabilities existed before the internet. IBM had SNA. IBM's PROFS even had an email system that existed before Microsoft.

For IBM PC systems there was something called serial communications that could be used to transfer data over phone lines.

Prior to floppies there was tape, as in magnetic tape, that has existed for more than a half a century. Magnetic tapes were relatively inexpensive.

It was totally possible to send a floppy in the mail.

First note that the question implies that 5.25" 360K disks was the beginning of computer programming and it was not. Before IBM designed the IBM PC, IBM had already designed and implemented many computer systems and operating systems.

Sophisticated communications capabilities existed before the internet. IBM had SNA. IBM's PROFS even had an email system that existed before the IBM PC.

For IBM PC systems there was something called serial communications that could be used to transfer data over phone lines.

Prior to floppies there was tape, as in magnetic tape, that has existed for more than a half a century. Magnetic tapes were relatively inexpensive.

It was totally possible to send a floppy in the mail.