While the same thoughts crossed my mind, I think he probably meant art in the age of mechanical reproduction.
Still, programming affords a combination of the widest reach and lowest barrier to entry: it rarely requires the artist, performer(s), or specific location(s) to be consumed as a medium.
I agree with what he meant, but I dislike his use of the word "only." I hate to be really anal, but that kind of thing always sticks out in writing to me.
"Hard distinctions make bad philosophy." as John McCarthy (of Lisp and AI fame) would say.
Still, programming affords a combination of the widest reach and lowest barrier to entry: it rarely requires the artist, performer(s), or specific location(s) to be consumed as a medium.