Could the internet exist in a way that makes the RIAA/MPAA/etc happy without DMCA? Maybe not. But there’s no reason to assume their happiness is a requirement, or even desirable.
The internet was more than fast enough for copyright infringement. Copywritten books, images, and even music were commonly shared online before the DMCA was passed.
Could the internet exist in a way that makes the RIAA/MPAA/etc happy without DMCA? Maybe not. But there’s no reason to assume their happiness is a requirement, or even desirable.