I think most people like the Discord interface enough. That's not reason to leave. The migration away is because it's an open source company, so Discord is poorly aligned with the company's values, and there is a constant search for better, more open alternatives. (They are migrating away from Google services as well.)
I really like the Discord interface for real-time chat. Nicer than Slack or IRC (and I'm comfortable with IRC, I used to be active on it in the old days).
The Discord GUI on top of a "modern IRC", specifically with publicly archivable channels, would be great.
But the way high quality information is constantly being posted then lost forever in practice is a big loss. Searching within Discord works if you know exactly what you are looking for. But you have to know, and wider searches such as with Google or any other tool that look through the rest of the company's online materials will never find the content in Discord. That's unfortunate as Discord tends to be where, by far, the highest quality and quantity of information is.
As a result of the company's migration away from Discord, we expect an abrupt discontinuity, as the new platform won't have access to the old Discord conversations. Then all the years of high value content people have put into Discord will effectively disappear, as nobody will search Discord when they aren't even using it any more.
What we'd really like is a gateway that allows the Discord content to be available in other platforms, generally searchable on the company's intranet, and on the internet for public channels.
If our Discord content was more openly accessible and shareable, even while using a closed source product, we might not be migrating at all. We'd probably let people choose their preferred client instead to access the shared real-time content. But it's not that accessible, and it's unfortunate so much expert knowledge will be lost in the migration.
Also, at my company we've really enjoyed Mattermost over the years. The main chat platform is open source, they make money by selling a paid enterprise plguin suite. All your messages are in a database you control, you can translate them to whatever you want.
Lots of customizations possible to make it to suit all your needs.
Why wouldn't Discord's support site say, "Meet us in the Support Discord"?
So now I can easily find a ton of clubs Discord servers and join them. These clubs would not be suited for a forum at all and they make more sense in a more "live" kind of setting. I see people in these club discords doing voice chats and streaming games to each other all the time.
It seems like this is more the target for Discord, but a lot of people have repurposed it for their own things like using it for their companies chats and support. It's no surprise that you need to use a ton of bots to make this better supported as Discord so far hasn't really focused much on that side of things.
Discord very-much seems like a younger generation kind of tool and a lot of older people come to it and try and make it fit other purposes.
Reading another comment about someone whose company used this for their internal communication is just crazy. While yes it is a good platform they should have known it was a poor choice with having their historical chat history locked into the platform.
I think any important and useful information should be stored via other methods. And I actually have seen this done as well. I've seen common answers to questions that will get added to some kind of FAQ style page online and that will be linked to when someone asks that common question.
Discord is pretty focused still on the gaming/community side of things and I think it does this part pretty well. I have seen it used to supplement many things. Many game servers have a Discord associated with them. Twitch streamers have their own Discord communities. Each game typically has at least one main Discord for it. Discord now supports discovering discord servers for clubs at your University. But in all of these cases I am mentioning being able to search this from a Google Search is not important. In fact in some ways I think it's preferred from a privacy standpoint to not have random chat messages I send be archived on random sites.
I think the problem is that people are trying to use Discord for purposes it wasn't really designed for. So it's funny when these people then complain about it.
This is my problem with Discord-instead-of-forums. I completely agree with your privacy point, I don't want or need every word I type recorded and crawled by every search engine. Ephemeral conversations are useful and important.
It's incredibly frustrating when a Discord server is the only avenue for help with a project. Discord, even at its best, isn't discoverable and is barely searchable.
It's not necessarily a new problem though. Ten years ago it was "find us at #projectname on Freenode". Before that it was join a mailing list.
What's amusing in an annoying way is groups are running into old problems but not learning from old solutions. FAQs were invented because online conversations weren't necessarily persistent. If you joined an IRC channel, mailing list, or followed a newsgroup at time t there was no guarantee you'd have access to any conversations that happened at t-1. So people would make curated lists of common, that is frequently asked, questions. These would end up posted regularly to those ephemeral communications or added to a persistent presence (web, FTP, etc).
I'd be far less annoyed by "join our Discord" if someone involved would persist some common or just novel questions to a persistent FAQ that's discoverable on the Web. It might not be as good as a wiki or forum but it's a lot lower friction than joining a Discord server to ask a question a hundred other people have asked.
With Discord you (or any user) can at least run one of the various off-the-shelf logger bots. And someone would still have to make it available, and who knows how nice it would be to consume, probably not very.
So I'm not sure either have much advantage here if the origin dies forever.