So, we gave a lot of thought on this use case over the years. The reason you have to write bots in Discord is because you are kinda putting a square peg in round hole, and doing this weird UX because there is nothing better.
On Discourse, you will be able to configure Discourse-automation to achieve the same use case, and be able to get the group/role assignment in ways that may make more sense for your users, like voting in poll or replying to a message in a chat.