That's fair, and thanks but I'm pretty tech savvy so I do know how to use the search function
I'm a member of 8 servers and what I described is the experience I have with 7 of those 8 (the eighth consist of three members!). I'm sure it depends greatly on the number of people participating and how regimented people are with segregating topics, but it's a fundamentally different way to communicate than a forum. Not that that's bad but it won't generally facilitate long-form thoughts, it will instead be quicker back and forth.
Two of the servers I'm a part of abandoned their forum because it was just quicker to communicate on Discord, but the members frequently make comments bemoaning the loss of historic conversation they were able to reference regularly on the forums, with many hoping the Discord server is just a fad. Think of how many times you look at an old topic on the Puritanboard---you really aren't able to do that on Discord unless you were there and have a good memory. There's just not as much lasting value. It's much more ephemeral.
On a forum I can look at a topic and decide whether I want to read any new content there or just skip it. I'm more in control of my time. On Discord (particularly General) there is no way to know what people have been talking and if I missed anything interesting so I end up wading through 120 posts since yesterday regarding football and some irrelevant news article before I find anything worthwhile. Again, this is only in general, it certainly varies based on particular user groups. It's great for near real-time back and forth though.
I'm not trying to bash your Discord server in any way, it may very well be the most organized and useful of them all