Seeing as he wrote the first version, was involved in the updates, and spends a lot of time promoting GPL, I would assume his views have a large influence in how it is used and perceived. GPL mentions software quite a few times and the preamble states "licenses for most software and other practical works". As I mentioned above, Stallman does not consider art as a practical work.

However, I am not sure how a judge or a lawyer would interpret the word practical work.