IANAL, but here's the bit where I explained this: "…allowing an app whose primary purpose is distribution of infringing content undermines fair competition among legitimate content providers."
To elaborate on that a bit more: Apple is a DSA-designated VLOP. Articles 34–35 obligate them to respond to risks on its platform (like apps used primarily for piracy) with proportionate mitigation. That's why EU courts (if they're ever involved) will find that blocking iTorrent is unambiguously a lawful and proportionate response according to the DSA.
