Because I don’t see a strong argument for piracy coming at a direct, immutable cost to artists. I also don’t see a strong argument that piracy reduces the chance fans will pay for art when the art is made decently easy to purchase and is being sold at a reasonable price. Of course there are complexities to this discussion but ultimately when you compare it to massive corporations wholesale stealing massive amounts of works of art with the specific intention of undercutting and destroying the value of said art by attempting to commodify it I think the difference is pretty clear. One of these things is a morally arguable choice by one individual, the other is class warfare by the rich.
Joe shmo torrents an album from a band they like, maybe they buy the album in the future or go to a band concert and buy merch. Joe shmo hasn’t mined some economic gain out of a band and then moved on, Joe shmo has become more of a committed fan because they love the album. Meta steals from a band so that they can create an algorithm that produces knockoff versions of the band’s music that Meta can sell to say a company making a commercial who wants music in that style but would prefer not to pay an actual human artist an actual fair price for the music. These are not the same.
(AI doesn’t create convincing fake songs yet necessarily, but you get my point as it applies to other art that AI can create convincing examples of, books and writing being a prime example)