I like the end result that ISPs are pushing back on this, but don't mistake this for altruism on their part.
Their businesses make money selling internet service. Were they to support cutting off those accused of piracy, they would be losing paying customers. Further, the business processes and support needed for this to function would be massively expensive and complicated. They'd have to hired teams of people and write whole new software applications for maintaining databases of banned users, customer service staff to address and resolve disputes, and so much more.
Lastly, as soon as all of that process would be in place to ban users for piracy accusations, then the next requests would come in for ban criteria in a classic slippery slope:
- pornography
- discussions of drugs
- discussions of politics the party in power doesn't like
- speaking out against the state
- communication about assembling
- discussion on how to emigrate
All the machinery would be in place once the very first ban is approved.