I know what you mean. Although Discord is, in my opinion, WAY better than IRC, I do miss the interactions and friends I made there. I miss forums as well, which is kind of funny because they still exist - not sure why I don't use them more?
Not that it matters to most users, because they wouldn't know how to use such tools to begin with, and don't know what they're missing.
Discord is an information black hole, and I pity future generations who'll have virtually no access to the petabytes of history lost in dark data vaults like Discord.
I usually connect to IRC channels through a browser client or a desktop app, but all too often, my browser would lose the connection or my computer would go to sleep, disconnecting me from the server. Also, sometimes the server would not let go of my disconnected nickname, so I would get one with one of more `_` appended to it.
Re-joining would not fetch the previous messages, and I would have anxiety that someone has replied to my message that I posted a few minutes prior, but I would never see...
I know that IRC bouncers exist, and I have even tried using `tmux` on a server to keep my irssi connection alive, but that is in no way user-friendly, even for a fairly technical person. Last resort is to find the public channel logs somewhere, if they even exist.
At that point, I would just give up and use Discord.
This far been a solved problem for 30 years. You just run an IRC bouncer on a host that's always up (like on a VPS) and have your IRC client connect to that. The bouncer will keep scrollback and logs for you.
Of course if you use Discord you don't need to bother to do any of that, so the convenience it offers is real, but it's not like if you're an IRC user you can't have persistent history.
On the other hand, with IRC you only log the channels you're in (unless you run your own IRC server), so you will miss out on history from other channels.
Now, most people might not have any interest in learning how to change the oil in their cars, and don't want to bother even if they have the knowledge. They prefer to hire someone else to do it for them.
So it is with Discord, where you "pay" for the service by giving Discord your data and handing over control over your communities to them.
It does appear to be discontinued at this point, but I do believe I've seen other ssh clients that do support the swipe at this point. I must confess though my use of IRC on the phone has always been relatively limited -- chatting in general on a phone is tiresome. Even SMS I do more in a browser these days on my desktop.
Matrix seems to bring along the features of Discord with the freedom of IRC. But, as usual when freedom is concerned, it does come with a fair amount of responsibility, particularly in the form of setting up and running the server.
That was true about ten years ago.
Most forums that keep their software up to date support logging in with a number of SSO systems.