Yes, definitely. Discord servers have basically all kind of text-channels that replace forum categories such as suggestions, feedback, bug reports etc.
I understand that communication through Discord is way quicker but I can imagine that activity on your website (forum) average time spent on page, amount of traffic, certain key words that are getting triggered because of people making threads and replying to each other and a bunch of other stuff are beneficial for your Google rankings.
Doesn't it sound like 'server owners' destroy their own free publicity through Google by adding all those chat functions to their Discord servers? I mean if I would run a private server I would absolutely not add suggestion tabs etc to my Discord server to stimulate people to use forums. I'd use a Discord server for quick communication only.
What are your thoughts?