As a result, many original cels were thrown away or sold. More critically, the master film reels for several episodes were lost, damaged, or destroyed during storage transfers. For decades, fans relied on grainy VHS recordings broadcast from Italian or Arabic TV stations because the Japanese masters were incomplete.
Sources: Archive.org collection "Mazinger Z (1972) Preservation Project," interviews with Go Nagai (translated from AnimeLand Magazine #45), and the Lost Media Wiki entry for TranZor Z. Mazinger Z Internet Archive
These scans allow English-speaking fans to read Nagai’s unfiltered script—where death is permanent and the line between hero and monster is blurred—for the first time. As a result, many original cels were thrown away or sold
Mazinger Z is owned by (Go Nagai's company) and Toei Animation . These are aggressive protectors of their intellectual property. In 2018, Toei issued mass DMCA takedowns against several fan sites hosting Mazinger Z episodes. Sources: Archive
We are in a "Golden Age of Lost Media." As streaming services fracture, and as physical media (Blu-ray, DVD) becomes a specialty niche, the only guarantee of a show's survival is a distributed digital archive.
Go Nagai once said, "Mazinger Z is a symbol of the power of humanity to overcome despair." The same could be said for the digital archivists who spend their weekends cleaning up audio tracks of the Rocket Punch or scanning brittle 50-year-old manga pages.