Discord really became big because it had 0 obstacle onboarding. In an age of Skype, Ventrillo, Teamspeak and Mumble, all "installation" software with "server addresses" and "setup your user config", Discord shows up, says "press this link", and done, you're ready to go. Install link? No, it's in the browser. Account? No, you literally got a temp account made for you. You just talked. Yes, with a button in the corner that says "Claim this account" which just wants an email and a name, but point is, you didn't even have to do that much. This is why the comparison to it is IRC despite the two being so far apart, IRC was the only other chat software with this small of a barrier to entry.
Everything else about the featureset was copy pasted from Slack. No one cares about that part.
I mean, I CAN see the value in pushing the context summary to git. We already have git blame to answer "who", but there is no git interrogate to answer the "why". This is clearly an attempt to make that a verb git can keep track of. It's a valuable idea.
I also seen examples of it before. I've got opencode running right now and it has a share session feature. That whole idea is just a spinoff on the concept of the same parent that led to this one.
Everything else about the featureset was copy pasted from Slack. No one cares about that part.