Discord's user experience is incredible compared to Steam. The app is super responsive. If they add video streaming as well they can compete with Twitch & Steam at the same time. Both have abysmal ux.
Steam on the other hand regularly tries to convince me that I am in fact not logged into the store despite being logged into the app (how do you even do that?).
Discord consumes a lot of memory. Steam makes my computer lag while not using as much memory.
Overall, I'd say Discord is a tiny bit better in the department of "not sucking" than Steam.
(And I still haven't forgiven Valve for killing WON, even if I know they had what they felt was a good reason for it)