Please, not another Slack walled-garden for discussion. Slack is both inaccessible and unsearchable, as well as a privacy concern.
Suggest to use already available open source discussion networks such as freenode and open software with accessible medium such as mailing lists powered by mailman and its archives.
If you insist on using a javascript-tainted webui for community discussions, use open forum software such as discourse ensuring it's properly searchable and archived by major search engines.
We actually had matrix up on running on a cluster built with Talos in AWS. We decided to focus our efforts on Talos instead of maintaining infrastructure. There is a convenience factor for us since it is only three of us.
It's just the few times I've used slack as part of an open community it's been suboptimal, honestly a freenode channel was and is better, anyone looking at something like Talos is likely to have an irc client installed :).
The beauty of Matrix is it's distributed, so it doesn't really matter if you're running your own servers. If someone joins from their own server (like I would from mine), the conversation exists there too!
