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.
https://en.wikipedia.org/wiki/Cat_(Unix)#History
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.