In an ongoing escalation of its fight against online sports piracy, media giant Canal+ secured court orders compelling DNS providers Quad9 and Vercara to block access to pirate streaming sites in France. Quad9 says that it’s determined to appeal what it sees as an absurd application of copyright law. For now, however, it will block the targeted domain names globally.
Because 99.9% of people are not going to maintain a hosts file, and don’t even know it exists. Not to mention you’d have to already know the IP of the sites you wanted to visit.
You’re basically arguing that phone books are a bad thing because people can just keep an address book.