I'm not aware what BGP is, clicked hoping to find out, was sorely disappointed.
A project page for a $language implementation of $protocol shouldn't be expected to give a basic description of $protocol. If you care about a new implementation, you already know what the protocol does, at least generally. If you're lucky, the project page links to a protocol description (possibly at wikipedia), or, as above, you can simply google it yourself and then decide whether a $language implementation of it is something you care about.
I mean, it already has a link to the golang website, but no mention of what BGP actually is.
After all, there is a reason it's called the wikipedia rabbit hole, do you know how often I start with a quick search and suddenly it's an hour later and I've learned all about $something-other-than-originally-intended?
On other issue, here's what typing BGP into Google gace me at the top: "Border Gateway Protocol (BGP) is a standardized exterior gateway protocol designed to exchange routing and reachability information among autonomous systems (AS) on the Internet. The protocol is often classified as a path vector protocol but is sometimes also classed as a distance-vector routing protocol."
Some things are hard to search for. Others, like BGP protocol, are so common you'll get it easily. Those can default on Google. Further, what use is a programmer going to be in robustly implementing the protocol if they can't figure that out? Hence the filter part. So, my position is more solid now that I Googled it.