I'd think that it's chaining together the characters in the file, catenating a file to the screen. Wikipedia claims that the first version of Unix did a single file.
Whereas "con"catenate means to link separate things together. These are minor distinctions, but if somebody is going to call things "asinine" they should at least get the pedantry correct.
The reference Wikipedia gives for that does not actually say that the original “cat” only took one file name. What is says is that “cat”s predecessor, “pr”, only took one file name, and that “cat” subsumed it.
