No voice, no proper file transfer and can't even see messages when you're offline meaning there's no reliable way of mobile notification means it's just getting too old.
A survey of IRC users would likely indicate that none of them care about it, and it's part of the appeal of IRC - I can only judge people by how they type and what they communicate. It's more or less impossible to tell anything about age, gender, nationality, etc on IRC unless someone cares to disclose it. It's far harder to mask anything like that in voice as opposed to text, so while you may consider it a fatal flaw, I consider it a feature. It's one of the better borderless sort of protocols out there for communication.
> no proper file transfer
What's wrong with DCC? Still works, last time I've used it. However, with a lot of the various free pastebin/image/etc hosting services out there, I don't see nearly as much of a need for that as I once did. DCC is a rare thing now, as opposed to a common way of shuffling files around as it used to be. So, again, based on "I literally make a living on IRC" sort of experience with it, it's not just a big deal anymore. Plus, an awful lot of people on IRC overlap with "I have my own hosting somewhere."
> and can't even see messages when you're offline
Bouncers exist, work well, and consume very little CPU or RAM. You can fit a freebie ZNC bouncer in the Google Compute Engine free tier (micro instance, 1GB transfer outbound), and might pay a few pennies a month extra if it's a really busy month. However, most channels are also entirely useful if you're only connected part of the time. I mostly use a bouncer to catch any PMs - I don't read scrollback unless I've been mentioned, and it works fine.
> meaning there's no reliable way of mobile notification means it's just getting too old.
Again, this only matters if you care about that. I know a lot of people, myself included, who have more or less rejected the modern "everything mobile" ecosystem with the constant stream of distracting notifications, and that IRC doesn't overlap with my phone is a feature.
However, there are plenty of ways to make mobile clients and ZNC interact such that you effectively have a modern style communication app, on a phone, with IRC as the backend - if you care to do so.
Yes, I'm aware I'm an older style greybeard at this point, but the very things you list as "ancient tech" are part of what makes it appealing. It's lasted for 30+ years so far, and I expect it will comfortably outlast most of the modern messaging clients, because it does what it does exceedingly well.
As for the rest, they work well on other services and you can simply completely turn off notifications if you feel it distracting.
It's just IRC doesn't have modern features when one wants.
Still wondering why people need to stick to it other than just because especially even after such a hazard.
The only benefit of IRC in my opinion is that sign ups are optional and might keep you slightly more anonymous but the again, most people would stick to a same nick anyway.
(1) It requires so little computational power on the server or clients that it's a lot more environmentally friendly than some bloated pig of a modern chat "ecosystem." I can still use old hardware easily with it. And, unlike most of the new chat stuff, it runs on low power ARM boxes nicely.
(2) It's lasted 30 years, and the Lindy Effect would argue it will remain relevant far longer than any of the hip new platforms of the year.
(3) It's not centralized. Discord is centralized. Matrix is less centralized, but matrix.org is still pretty effectively centralized for most cases. IRC is distributed, has been so, remains so, and it's utterly trivial to start up new servers.
Clearly, you see no value in it. And that's fine. Plenty of people see value in it, and... as one of them, honestly, a lot of the new people who show up for 5 minutes and then leave when nobody answers instantly are pretty annoying anyway. There's several decades of established culture, and it's quite easy to find writeups on the proper way to interact with IRC, but a lot of people don't bother and get irritated and then leave. Fine.
You appear to be making a bit of a "Other systems are better because they're new!" sort of argument here, and not everyone shares that viewpoint.
But Element, running on a modern machine, is using almost a gig of RAM. Hexchat, running on an older Pi, connected to quite a few networks, has expanded to almost 100MB.
