I can confirm this. I wrote to authorities and received a reply that only site maintainers can apply for unblocking. Block was related to Telegram ban.
github is not always a solution, because some projects located at git.openwrt.org are needed to be downloaded at times. Not only feeds and luci that are also available at github.
It is easy to workaround by using IPv6, vpn, proxy or other ways.
But maybe somebody can write to RKN to unblock the address? If there is nothing Telegram related on that IP, they'll unblock it.