Unless the public puts literally billions of dollars into funding and expanding public libraries to catalog all this video media into numerous publicly owned gigantic server farms that maintain the capacity to upgrade digital storage indefinitely, all video media is doomed to stay with privately owned capitalistic multinational corporations that are influenced by foreign governments to censoring various things at will, and all video media is destined to die forgotten and overwritten by future shitty memes and useless influencer garbage.
If your DNS sinkhole is down, your modem/router/host operating system settings (and even the PiHole itself) should allow a fallback. If you didn’t set that up and don’t know how, then you should consider not using Pihole until you know what you’re doing.