APIs have been getting documented recently and you can say all of them are now documented on the API side. The specific problem you posted as an example is a rare case. It is not fair to say everything is like that. And that specific problem could be solved by hived returning proper error messages.
So, API docs have gotten better and they are in a very good shape compared to what we had. That website, https://developers.hive.io, is a bit of a mess and it always needed work. And it has been getting some work done by blocktrades team.
Ranting to your rant about weeding out people.
We don't get new users. We have not been getting new users for years now. Our "developer user base" has been the same people for years. The discord you posted is an example of that. It is shrinking and not expanding. The owner of that particular discord has left Hive years ago. The other developer space, a mattermost server managed by guitlyparties, has not been growing either.
The solution is and has always been to get more users. More users will solve majority of our problems.