I’d like to clarify several points regarding Discord usability that were brought up:
That’s not entirely true. The only thing you need to read chats on discord is a have a username (that does not need to be unique across the whole discord population). As an experiment: open a private browsing window in your browser and go to https://discordapp.com/invite/rust-lang. Enter a random sequence of characters as your name. Voila! You can now read the chat!
Discord saves all the history, and has a decent built-in history search support. It is feasible to make a bot that would back up all the history if you wished to.
This is my personal opinion, but I don’t think chat logs (be it IRC, gitter or discord) are important enough to cause damage in case they are lost. They are primarily useful for near-real-time discussions and instant feedback. Any summaries and decisions resulting from said discussions should be posted in lower-traffic places such as github issues (or this forum).
That said, again, there are means to export the history in case you wish to abandon the platform.
All the points sans the last one stand for discord as well. (It does not feature e2e encryption, but I think neither does telegram by default, and not for group chats. Regardless, as you’ve mentioned this is probably less needed, given the desire for the chat to be publicly accessible).
Near-real-time chat platforms as a whole have poor support for links. Discord technically supports those, but I’ve never seen people actually use it. So I’d say the fear of people sharing links to discord discurssions and those links becoming obsolete is unfounded.
Again, it’s much better, instead of linking to conversations held at fast-moving chat platforms, post summaries of said conversations instead.
This low friction aspect is also present for discord. Again, just go to https://discordapp.com/invite/rust-lang, enter any username (as you would in irc), and done. It is true that you need to confirm the email to chat (i.e. to send messages), but that is because Rust team set up the server this way, not because it’s discord’s will. In other words, the email verification can very easily be turned off if Rust team wishes so.
Note, I’m not saying that Discord is an ideal platform, that’s strictly better than all the others, but merely that some of the criticism and perceived inferiority to other platforms is not entirely true.