I shall not today attempt further to define the kinds of material I understand to be embraced within that shorthand description ["hard-core pornography"], and perhaps I could never succeed in intelligibly doing so. But I know it when I see it, and the motion picture involved in this case is not that.

1964 - Supreme Court Justice Potter Stewart

Aside from the content, the article says that the band/label got no releases from the child’s parents. That in itself is a huge problem, and hard to believe a major label would market an album with no releases.
When I bought the record when it came out in the early 90’s, my first thought was “I wonder when the baby in the photo will sue the record company”. Now I know.  I will say the record cover is NOT child porn or any other kind of porn in my opinion.  That is like saying the statue of David is porn.