I’m sure they report serious crimes and at least retain records for questionable activity.
I don’t get visibility into internal Discord operations, though. We just see that the perpetrators lost both their Discord server and their accounts disappeared from other Discords they were in. They angrily returned later with new usernames.
That would be a tremendous amount of work, at best they might be forwarding it to some CERT. But I doubt even that. Shutting down the accounts is probably the best they can do.