Online forums in general seem to be declining in popularity imo. There’s still value here for certain types of content, such as written tutorials and blog posts which would otherwise get lost in the chat history fairly quickly on Discord. Also for those that prefer the forums format ofc. But for faster support related topics, I agree that the Discord is probably your best bet at the moment.
The speed of responses is also down to the ratio of volunteers - the player support forum still seems pretty active, but the coding ones much less so. Once you’re feeling more confident in your modding skills, be the change you want to see