Discord isn't really a Slack competing product as much as it's a Teamspeak and Mumble competing product... or at least at the start.

Initially it was just easy to use VOIP with rich text chat channels. Now they've added in video calls and a video game store meaning they're more gunning for Steam and even less for Slack.

I do not see them as being Slack competing. They're too casually focused to be a threat in an enterprise environment.

I completely forgot they added the video game store. That would kill them as a consideration for any kind of corporate environment.

If they were targeting themselves to that space, that would be an administrator toggle without question.

Default Windows 10 comes with preinstalled video games, much less a store. Discord already has subscriptions, at some point I see them selling a version with enterprise features.

I don't think anyone considers Discord a competing product. It targets a different market/userbase than Slack.

Slack is very much setup for business use and integrations.

Discord has a bot API, but it's mostly focused around realtime chat for communities (like a community-focused Skype).

They're very similar, but serve different purposes and different markets

I wouldn't say they compete directly as one is obviously targeted at corporate and the other is targeted at gamers. But they are extremely similar and even the UI, while themed completely different, is extremely similar.

Essentially the exact same app but with voice channels for talking to people alongside the text channels.