Try going to https://libera.chat/guides/clients and reading through that page, and keep track of how many words a non-technical user would not understand.
From the very beginning there's jargon. The page does do a good job of explaining the jargon though, so they get points for that. However, if you're a new user, the difference between this 365 word wall of text full of new words and strange client names is striking compared to e.g. Slack's obvious "TRY FOR FREE" button.
> "keep track of how many words a non-technical user would not understand."
And it's not just the words on their own; the instructions and wider context are strewn with internal techo-details, there's no step by step path through them, no strong recommendations; given this is under "About IRC" it starts with "choosing a client" as if you already know what that is and why you want one. Paragraph 2 is about SASL. ("repository of instructions" - why not "instructions"?). You're a "connecting to IRC for the fist time", you click the link to the preferred authentication method. "SASL is a method that allows identification to services (NickServ) during the connection process, before anything else happens - therefore eliminating the need to /msg NickServ identify" - word salad. A way to eliminate the need to do a thing you've never heard of and don't know why you'd want to do it at all. Nope back to the main page.
"If you're interested in ensuring the security of your connection" - am I? Should I be? I don't know what "my connection" even is in any practical sense, or what the consequences of it being secure or insecure are - click the link; "'is using a secure connection will appear in WHOIS (a 671 numeric)'" ... what? "In order to verify the server certificates on connection, some additional work may be required. First, ensure that your system has an up-to-date set of root CA certificates." nope back out of that.
"If you cannot install apps on your computer, you can use a web app" - I don't know if I can install apps on my computer. How can I use a (web) app if I can't install apps? Is this web app Google? Can I not use the web app at any other time?
"Kiwi IRC is a popular free web client that you don’t have to sign up for" - the first time 'sign up' is mentioned is to tell me I don't have to do it. Then why mention it?
"a popular web client service that keeps you connected after you close the page..." - technobabble word salad. What's a "web client service"? It keeps me connected, what does that mean? It sends me notifications or something? Why do I want to be connected after closing the page, isn't closing the page my intent to leave? So it's an infection or something, does it hack my computer to stay there? How do I get rid of it?
"...and has a limited free plan" - what are the limits? Is it good enough? Presumably not - if the limits were enough you wouldn't mention them, right? You don't mention 'free plan' before or after, does all of this cost money? Any of it?
"Graphical clients - These are clients that you navigate primarily with your mouse cursor or touch" - what non-technical user thinks in terms of "navigating"? Graphical, if I want graphs? Graphics? Pictures? Those are good, yeah? Surely, surely the kind of semi-technical/poweruser who might be about to use IRC for the first time is the most likely to use keyboard hotkeys in GUI programs?
"They can be installed on your device directly or accessed in a web browser." - you just told me I had to use the web browser when I couldn't install a client, now one of the clients is in a web browser?
"Terminal or text based clients are clients which you primarily navigate with keyboard shortcuts. As these typically do not need mouse navigation, [...] WeeChat is a popular terminal client which has an experimental mouse mode option" - ???? I'm a new user to IRC, non-technial apparently, and I'm already into the experimental options in one specific TUI client. Steep.
"Bouncers are clients which act as a hub between other clients and the IRC network. They allow you to see one connection from multiple places" - ??? Words. About a thing. Bouncers guard the door and keep bad people out?
There's a big pink call to action "connect" button in the top right, which is a surprise dropdown offering a TLS connection, a plaintext connection, a "How to Connect" option, but despite being a web page with web hyperlinks, none of them are links to web clients that actually connect to anything. Even knowing IRC, I'm surprised, I was expecting an instant CGI gateway link or something. (Remember, web clients are the things you use if you can't install apps, or if you want graphics, and you want graphics if you navigate with a mouse).
The menu on the left has "Helping you connect" which has "Using CertFP" above "Connecting to Libera.chat", because creating a self-signed certificate using Cygwin (which isn't explained or linked) is more helpful than the address of Libera chat?
It must be possible to run this kind of page past a hundred "non-technical" users via Mechanical Turk or similar, and have them circle the places that are confusing or they don't follow?
And tell them how to register the nickname, and tell them how to log in, and tell them how to list rooms and join them. Then teach them about op codes.
(Lack of) Ease of use is a big reason for IRC's loss in popularity.
You don't need to register a nickname (I didn't when I used freenode)
In the clients I mentioned listing and joining rooms works the same way it does on discord and slack: you open the list and click the ones you want to join.
Registration is a bit of a sore point (and is being worked on in the IRCv3 WG), but login, ops, channel listing, etc. afterwards isn't - that's all handled quite well by modern graphical IRC clients.
Discord/Slack already has a bunch of those things- how to mute channels is a big one, as well as how to change ones nickname, how to get a role, and managing permissions for various channels.
You mean handing them xchat/colloquy/kiwichat and telling them to come up with a name and click this text box to send a message?
Sure irssi is hard to use but unlike Slack and Discord you're not stuck with a single terrible client.