The DMCA process is pretty good. All you have to do is counterclaim and the host/platform can put your content back up unless the claimant actually files in court. Also, without the safe harbor protections, it would be almost impossible for sites to allow user content at all, because they'd potentially be liable for infringement of users.
ContentID goes way past DMCA requirements and proactively allows copyright holders to have content automatically taken down, without a clear and fair process to appeal, and without due diligence that holders actually legitimately own the content they're claiming.