Obviously discord is different than only mumble alone. Discord is not very different from mumble + IRC, which is what we are comparing to and what I said in my post. IRC of course does have history if you keep your client open which most people do.

Most organized gaming groups used mumble/ts/vent and some combination of IRC and forums. The only difference here is that they're physically in the same app, and of course, there's embedded stuff which is just generally technical iteration (some IRC clients had it). Otherwise IRC always had channels and DMs and mentions and multiple servers. Only setting up your own server wasn't free -- you could easily hop on any network and create as many private channels for you and your friends as you wanted. Yes, older technology wasn't as accessible but at the core it's the same feature set.