It's interesting that in 2016 the top comment was about how out-of-date the documentation was, which made it very challenging for the novice to approach. When I did it in 2019, my experience was very different -- I marveled at the quality of the instructions and documentation, as well as how up-to-date it was.

In fact, just this week I was googling for some information about building GPG without having to deal with generating PDF documents, and I stumbled upon an LFS GPG page[0] that had been updated that day. There seems to be a fairly active community who is maintaining the guides.

[0]: http://www.linuxfromscratch.org/blfs/view/svn/postlfs/gnupg....