I personally don't think Slack is a great product for open communities. While I don't think they're actively hostile to open communities it's certainly not thei

I personally don't think Slack is a great product for open communities. While I don't think they're actively hostile to open communities it's certainly not their priority from a feature perspective. In my view, Slack is an enterprise product, and Discord is more of a commercial product. It's very difficult to be both and gain necessary market share. There's also the tangential fact that open source shouldn't be relying on proprietary communication protocols that are difficult to migrate away from or make it difficult to maintain anonymity.