With that said, i agree that no one "cares" about Discord. If a better thing comes along i could easily see people dumping it. But, i imagine it'll be a bit more difficult. Discord "won" in my view because it simply had to be modern to be vastly superior. However, i'm unsure how easy someone can make a next version that is such a superior leap.
Fwiw, as a gaming voip/chat i still find it a pretty great UX. My only complaint is that it is a bit laggy due to the, i assume, web-based interface on "desktop".
The last time I used Slack it was a giant memory hog and used a lot of CPU resources. I don't think Discord would have become nearly as popular compared to say Mumble or Teamspeak it was not also relatively efficient in terms of system resources because PC gamers are very sensitive to big resource hogs.
As far as becoming a digital retail storefront, it has zero advantages compared to the other various competitors. While the other digital retailers do have social features, those social features are generally add-ons that aren't critical to the experience. Many of those storefronts also have API hooks that many developers rely upon for certain game-relevant social features like joining a friend's game in progress.
Discord "won" because it's literally burning cash and offering a service for free (for example, I don't have to pay for a t2.micro instance to host a Mumble server). But this is obviously not sustainable.
If you're selling a dollar for fifty cents, it's not hard to find a market.
My friend circles on discord have enough people with nitro that it's almost certainly cash-positive by a lot.
The price wasn't the issue (imo), it was simply the user experience. It had the best, by leagues. Users (ie, non hosts) didn't pay for any of these products, but the UX of Discord was vastly superior in my view.
I'd rather install something compared to using the "webapp" version if it used 30 MB of RAM rather than 3000MB.
You don't think Discord has any lockin? For a lot of games, coordinating voice chat these days is "paste a discord server invite in chat". Pretty much any guild/clan/subreddit/group/whatever has a Discord (apart from ones with really old TS servers etc), so if you're in one of those, you probably have Discord. Much easier than negotiating Skype/Mumble/TS3.
I'd say Valve/Steam is feeling a lot more pressure these days than Discord.
I'm not sure Discord will ever be a hugely valuable company, but judging by the fact that every launcher in existence (Steam, Battle.net) is trying to clone their features, I'm sure they can at least sell it for quite a bit.
I was really expecting them to push out of the gaming niche, but with the store it looks like they're doubling down on that angle.