I wonder if the name Smalltalk was inspired by the name "Lisp". Lisp is away of talking, so is small talk. Maybe creators of ST-80 desired to create something higher level, more human-like than "lisp".
"LISP" gets its name from "list processor".
"Smalltalk" gets its name from the the fact that the language came from the Learning Research Group at Xerox PARC -- the "small" was thus meant as an acknowledgement of the study that how children learn was crucial to the design of the Smalltalk system, and the "talk" relates to the fact that objects "talk" to one other by messaging.
The graphical debugger, dynamic code loading, bytecodes with microcoded CPU configured on boot, REPL with access to the whole OS, the way OS, libraries and applications blend together, all there across all those language stacks.
> As for hype: Another motive for "smalltalk" was the practice at the time of naming operating, and other, systems (which hardly did anything) after mighty indo-european gods, such as Thor, Zeus, Odin, etc. I figured that if Smalltalk ever did something neat, then people would be pleasantly surprised.