I hope that builders will open up forum threads before making large modifications to the site, but the worst-case-scenario possibility of the future formation of a cabal that holds unrecorded discussions with almost no community input on a different site about how to run Danbooru has me kind of uneasy
I did consider this when I made this server. I do very much agree, it's a cornerstone of our community that all decisions are made in public and that everyone is able to give their input. The lack of hierarchy and the fact that anyone can (theoretically) get involved in decision-making is a vital thing. But in practice I think the culture of the forum greatly discourages new people from getting involved. That is something I hope the Discord can help with.
I think Discord is another step in this direction. The barrier of entry is higher, because instead of just clicking on the "Forum" link, a user has to install and configure a separate program before they can join the discussion.
You can use the web app (I do). You don't have to install anything. Admittedly you need a Discord account.
Most Danbooru users only set foot in the forum when the site breaks (the api limit bug, for example). We've set a precedent where "consensus" means "a handful of builders plus a mod or admin have signed off on it." So a small number of power users control the direction of the site with little input from the larger userbase, which doesn't seem to care enough about the decisions being made to get involved.
This is entirely our own doing. The culture we've cultivated on the site actively encourages this. Theoretically the forum is open to everyone, but in practice it's not easy to get started at all. It takes a long lurking period for new people to get comfortable speaking up. Even the most fundamental things, like requesting aliases and implications, are not well-explained.
When it comes to policy, we have over ten years of past precedent you have to be aware of. Most of our policy is not documented anywhere except in years old forum threads, which often died with no clear resolution to begin with. Even longtime builders are frequently confused as to what our policies are. Is it any surprise that our decision-making is so dysfunctional and that so many threads deadend when none of us know each other on a friendly level? It poisons discourse when your only interaction with people is bickering with them over stupid shit on the forum. It turns every discussion into an argument that must be won, instead of a conversation.
The "serious business only" nature of the forum is discouraging and intimidating for new users. It's also extremely time-consuming for those who do get involved. We've lost many active forum-goers over the years. In the past year, I can count on one hand the number of new faces we've had come in to replace them. That is a big, big problem.
Rant over. My goal with the Discord is not to shift things behind closed doors. It's the opposite, it's to foster a community so that more people get involved with the site. Danbooru is my home, but I find it deeply disappointing that in the ten years I've been here we've never developed any kind of real community.
PS: That lack of chat logs is a problem. I will look into saving the logs and making them public (which, by the way, the irc doesn't seem to have either).