I started programming in 1968. I was working in the R & D department of a computer manufacturer, in the disk drive development department. We had to write assembly diagnostics programs in order to do our work. I fell in love with programming switched and never looked back.
In assembly programming, our 'arguments' were all held in registers, or internal (core, no affordable silicon back then) memory, but they were indeed arguments. I don't, however, remember calling them arguments back then.
A function could return a single item, but that item could be an 'address' to a structure containing many elements. So in a way, we did indeed have multiple arguments.