IRC is older than World Wide Web, and unfortunately there wasn’t as much innovation over years.

It was designated for a live chat so thought of also storing history and replay it didn’t make sense then (the reasoning was that if you needed to send something that’s not live, why not use email?)

Though people come up with own adhoc solutions like for example mentioned bouncer, some networks also had memo service where you could leave a message and there were also bots storing channel’s log.

If features like these are important to you, I didn’t think you will be happy with IRC, adding them would require rearchitecting the whole thing.

You can see for example slack doing it (it is heavily influenced by IRC although it evolved so much that maybe that is less visible now)

I didn’t have a chance to play with it yet, but I heard Matrix could be the successor to IRC.

Nothing against IRC, I spent years on it and loved it, but it isn’t great if important features for you are things like chat history when you were offline, embedding pictures in chat, threads, audio/video chat etc

The things where IRC still rules is: simplicity, very low resource requirements, and no accounts need, just pick a nick and you are in (this is also why keeping history for each user is so hard to add, when servers didn’t really handle accounts.)