I know that most "man" pages are formated using Perl, while Go is a recent language made by Google. If you check OpenBSD Github repositories, you see that, contributions are not made in Github but throught the mailing lists or by sending an email to the @Tech guys, who control the flow of OpenBSD development. I think this approach is different from many others, since the majority of projects development, happen at github, by opening a issue and discuss it, or by opening a pull-request, with some updates to be implemented in the main project, as a new funcionality or a new feature. If you see OpenBSD contributors, you can see that, all the changes are discussed outside Github platform, while in the end, this changes will be done in the official repositories that store OpenBSD source. The more I use this OS, the more I feed "safe" on using it, while the OS limit hardware resources usage, this limitations are active to block known attacks against hardware (Intel) or against software, like for example (OpenSSH). They are known to be one of the most secure Operating System in the world, mainly because it is Open Source. Cisco that is not Open Source, is part of the flow, where OpenBSD is used. Cisco systems are as well, secure systems, while being propretary, Cisco systems have some limitations, like OpenBSD have, while OBSD offer a Full OS to be used by anyomne, Cisco systems don't offer the same, but only the control of network flow stacks. I remember to do the CCNA 1 and 2, which is a certification to define Network Routing and learn about IP subneting, there is no GUI interface to manage those, but only terminal / console interface.
The Go lang is not installed by defaul on OBSD systems and Perl is, since is the language that will format the man pages and control many other details and funcionalities of the OS. While Perl have some years (more than 20), Go is a New language in the market and is used to create many solutions, that anyone can explore in Github and other platforms of code hosting. Go lang, in my non-expert interpretation, is like Rust, since there are a bunch of libraries that we need to install and compile, each time we wish to install new packages, while Go is already precompiled, Rust libraries, need to be compiled against the new package, every time we wish to install new packages or update them.
Which language is more secure?
This question is tricky, since the most secure languages, are secure because the developer understand the flow of each language. All languages can be secure if you master them, while is true that languages that have more control of memory like C, can be seen as being more secure than Python for example. This days, many developers see Rust as a secure language, since it was implemented in Firefox and Thunderbird for example, while Rust language is very recent language if you compare it to C or C++. But once again, you can create unsecure applications use C or C++, because you don't master memory control and without master it, you will design a product with many security flaws.
Anyway, this is only a small article that speak about few things that OpenBSD developers use, in their daily lifes. Some of them, have projects that are not included in OpenBSD by default, while being just "Code contributors" of OpenBSD project. I see this interesting, just because we(I) can imagine that OBSD developers, dedicate their time to OBSD only, which is not true. OBSD is as well, a project that feature up other projects, like NetBSD, FreeBSD and others less popular Operating Systems, like HardenBSD.
Some of this developers, are developers of LLVM, which use as a Logo, a Dragon, and naturally the "Dragon" is as powerful this library is. Anyway, put away my creative mind that likes to play with this kind of symbology. LLVM is a powerful language that create stability for BSD systems and Linux systems too, mainly when the use of GUIs are one of the objectives, like making use of QT or KDE, Gnome and others, since LLVM is needed to build the X and add Mesa abilities to deal with Graphical drivers.
Just more "bla bla bla" that is "bla bla bla" if you don't think about what this "bla bla bla" means. ;)