Generally the fun phase of a consumer-facing social company does not last forever though, and I'm not looking forward to the phases that often seem to follow. We can look at anything from Reddit to Youtube to Facebook to see the types of issues that lead social products to become increasingly user-hostile over time, and I'm not confident that Discord can avoid the pitfalls that have led to the decline in quality of most similar products.
The issues that often lead to the increase in user-hostility have many different causes and manifestations, but they often start with an increase in monetization, often with vast troves of user data, of which Discord is obviously not lacking in. As the platform grows and controls the social lives of hundreds of millions, there becomes increased demands for censorship, not just of political and ideological nature, but also for the purposes of copyright and IP, and the from multitude of governments that they must work with (obviously including, but not limited to the US). Discord already has very strong network and gate-keeping effects in many communities, and social ostracization is faced by users that contemplate not using it; losing network effects once you have them is generally not very easy, so it will likely be the dominant player in its area for a long time.
I don't want to just sit here and spread negativity about potential issues, but seeing an entire generation of people use yet-another-social-product, it does have me concerned from time to time. I really do want people to be able to communicate directly with one-another, without multi-billion dollar companies sitting in between users, reading and storing their logs, every click they make, and gate-keeping access to begin with. We've seen some of the places this can lead, and many of them aren't very pretty.
Regardless, Discord has made a great product that strongly beats its present and past competitors (which is what I'd add to the full article above - competitors like Skype were really bad! From excessive ads to laggy calling to leaking user IPs, which it still does), and for that I'm grateful that there's such a better software alternative for communities and friends to get together with. But I would definitely love to see pro-active work and assurances from Discord that help to convince me that they will be a unique force of Good in the consumer social space rather than regress to the mean that we see exists today.