It doesn't, but platforms basically do everything they can to claim the various common-carrier liability shields in DMCA-like laws. In the U.S. that means they forward the takedown request to whomever generated the content, and in theory should allow that generator to comply, or publish a counterclaim.

The whole system falls on the floor though when the common carriers aren't, and have low quality processes that don't actually enable the counterclaim half of this process.