Yes, we run our community entirely on Discord. We run our support functions through our website so we have audit trails but all chat goes through Discord. All our user roles are synced via Discord OAuth2, so we no longer have to update user roles in multiple places
We found Discord was perfect as we wanted real-time chat, as especially with games, the ability to just 'hop in and play' is really important.
I have ran normal forums before, and we have had forums before for this community, but we found our members just stuck to using Discord.