With mentioned problems of
- Broken links, not founds, redirects covered by a single monthly crawl thus being regular and benefitting all projects at once. - Size, could apply common compression such as xz or even ZSTD to entire mirrorable local archive. Similar for video materials.
http://open-zfs.org/w/images/b/b3/03-OpenZFS_2017_-_ZStandard_in_ZFS.pdf https://www.youtube.com/watch?v=hWnWEitDPlM