As much as I hate discord for anything other than strictly gaming and fun, if your user demographic is primarily kids, teenagers and young adults I think Discord is fine. They're already on it anyway and you have to meet users where they're at. If I were to ever choose discord it'd be in this kind of situation.
I'm 44, so for me a forum is ideal, Discord is way too intensive.
Then one of my members started a discord years ago and a lot of members went there. I switched everyone to an official one, and one member volunteered to moderate.
I would say most questions come from Discord, then YouTube comments, then email. My own forum wasn't as popular so I closed it due to lots of spam that I had to manage.
I also pushed hard for Reddit but never took off (I liked reddit more)
One thing to mention that is probably important: this is in gaming sphere with lots of kids, teenagers and young adults. Also used in schools by teachers.