There has to be more to it than a pure loss leader, since there's also the Bandwidth Alliance Cloudflare is in, which allows R2 competitors like Backblaze B2 to

There has to be more to it than a pure loss leader, since there's also the Bandwidth Alliance Cloudflare is in, which allows R2 competitors like Backblaze B2 to also offer free egress, which benefits those competitors while weakening the incentive for R2 somewhat.