I understand the issue you are describing as it regards to resources and time devoted to the care for MonoGame.
However, I believe I volunteered to help with the development of documentation a while back. However, what I would be interested in doing is taking the API and posting documentation for each class and its properties and methods with examples on how to use each. In fact, this type of documetation appears to be lacking with every Open Source graphics engine available. The result is that people who would like to try their hands at game development have no way of learning the fundamentals.
For example, it has taken me months of research and experimentation to build a credible hexagonal map-board that is similar in style to that which John Tiller Software uses with their historical combat simulations. This type of effort would no doubt discourage many people from pursuing such development.
Instead of using the existing site for such work it may be better to set up a new WordPress or a new Wiki site where the style can be fleshed and developed for such documentation. Each API segment would simply be a post or a page to a menu for example.