I've now built a registration system. It's not linked from the site yet as I do not have any robust spam protection set up, it's only accessible by inputting the url. If you've already been in contact with me on any other site you can ask me for the link.
The system uses Discord Oauth for authentication, just in case bots find the link . The oauth is only for authentication for now, I can set up oauth login in future. Now that users are able to register, you are also able to make new topics and reply to existing ones. No need to feel hesitant, that's what I'm building this for. Feel free to share your thoughts and help guide the direction of development.