Still harder than Slack, right?
The main thing that worries me about is discord is their revenue model... I just don't see how they're making money, and they keep on raising money.
There are a few good alternatives like zulip [0], matrix [1], discourse [2], Rocket Chat [3], or just plain old irc.
Although discourse isn't really a chat application but more of a open source forum software.
[2]: https://github.com/discourse/discourse
[3]: https://rocket.chat/
[4]: You can get around this by messaging relevant information to yourself. Or just saving things locally, like a weirdo.
I never said anything about Slack or Discord being better/worse than each other.