I think you hit the nail on the head. The reasons Discord works well for you are unfortunately ... why it won't work for me. (I'm a late 30s male, but, I don't play video games. Nothing against games or gamers, I'm actually jealous! Just never found anything fun since Zelda and Tetris)
I loathe seeing something I'm interested in, something math/science or technology oriented, on Discord. Quoting, and agreeing with you, "I think it's way better to use a system I am already signed up for." I don't want to sign up for a friggin Discord, or a Telegram, or a Slack, or a Whatsapp, and who knows how many other variants of IRC, just to find information!! I have "account fatigue".
I already have a web browser!
Why should I create an account on some closed source platform (that will probably collapse in 5-10 years like all of them), and learn yet another style of markup and communication and lingo...
It's much better for this information to be on a webpage, possibly a web archive of a threaded email list, or a subreddit. I can read the thread, get my answer, then close the tab without carrying around a basket of one-off bullshit accounts I created to join a plethora of chat rooms. And when I leave, it's worth noting that the comments/questions are still on the page, and indexed by a search engine for those to find after I'm gone.
Compare with discord, where it's ephemeral and behind a walled garden. Even worse, I think proliferation of discord chat rooms might suck the useful people and information away from areas of the internet I can easily access, and hide them somewhere hard to get.
I'm appreciative of your comment and glad you made it. It's good to be reminded that kindred others enjoy the "other side", but remember it slices both ways. :)
"Discordization" makes it more convenient for you, but at the cost of making it less accessible for others. I suspect the bulk of your happiness with it derives from your early presence in the ecosystem, not because of any strengths of the platform itself.
A possibly better solution would be something that doesn't put up any barriers to entry for any of us. :)