With pdf of this size, it would be easier to use Google Drive viewer instead of directly linking the pdf file, so that users on both desktop and mobile devices can view the pdf inside the browser.
Gopher doesn't support encryption. There is no standard for gopher over tls.
This makes gopher irrelevant for encrypted communications.
But what makes it great: gopher is simple. You can use curl or even netcat for browsing gopher sites.
If facebook hopes the new compression algorithm to be a standard, why doesn't it publish an IETF RFC draft? Will it follow OpenDNS way of dnscrypt by open-sourcing the reference implementation without publishing any IETF RFC draft?