After all, there have been computer-generated writings and music for even longer than that.

In "Computer Music", Scientific American, Vol. 201, No. 6 (December 1959), pp. 109-121 , available at https://www.jstor.org/stable/pdf/24941187.pdf we can read about 'chance' and 'almost random' music:

> A second and rather well-known example of chance music is Mozart's "A Musical Dice Game." This piece, one of many similar "compositions" produced as parlor games in the late 18th century, consists essentially of several dozen as­sorted measures of music, the order of which is determined by rolling dice. A more modern random work, "Imaginary Landscape" by the American composer John Cage, is "scored" for 12 radios and thus derives a strong element of random­ness from regional and temporal varia­tions in radio programs. ..

> John R. Pierce of Bell Telephone Lab­oratories, an authority on information theory, has demonstrated other ap­proaches to the composition of simple "probability music." In one, a sequence of chords is chosen by means of dice rolls and a table of random numbers; in another, a series of volunteers each con­tributes a measure. A number of Euro­pean composers have produced more elaborate random music electronically by causing random sequences of electri­cal signals to trigger sequences of tones. ...

It then goes on to describe how the author worked on the Illiac Suite for String Quartet.

Again, this is the 1950s.

https://youtu.be/sJtm0MoOgiU

What would that count as?