To use Discord in good faith and with open eyes, you have to prioritize communication in the present, and give up hope of archiving anything that was said for people who might need the information in the future.
That's only half true. Yes, Discord does allow a "rich" chat experience, with channels and servers, but there the similarities end.
IRC is based on an open protocol, with many open source clients available for it, and a decentralized server infrastructure.
Discord is closed and centralized, with only a single client available for it.
You can easily log IRC channels, but there is no easy way to do that on Discord, if it can be done at all.
I've logged every channel I've ever visited on IRC, and I can use powerful text tools to regex search through all of my conversations on IRC and have the results appear instantly. Nothing remotely like that is possible with Discord.
Paging through IRC logs is virtually instant on a modern terminal, while Discord makes you wait a long time between every other page load, so if you need to look through more than a handful of pages it's incredibly slow and painful.
Some IRC channels have their logs published on the web, making them fully searchable through web search engines, but to my knowledge no Discord channels do that.
What happens in Discord stays in Discord.
Its a shame its being used for general communities who don't use or need the voice chat feature. Especially when its an official community for a place, given their stance on third party clients and privacy issues.
If you don't need voice chat, Zulip, Mattermost, Revolt, Discourse, and many other would suffice (Linen recently got featered on HN). If you do, I think even Signal would be suffice these days.
For Discord search, recently Answer Overflow was recently featured on HN [1].
I just googled "how to use openllm" as an example to test your thesis, and the results look very relevant to me.
https://www.google.com/search?client=safari&rls=en&q=how+to+...
"Showing results for how to use openlm
Search instead for how to use openllm"
They stem words aggressively, so searching for "repeater", which is a less common, specific term, gives you results including "repeat", a commonly used word. And there's no way to do an exact word search.