In 2025, a company using IRC to communicate with its users would be like using ham radio. Sure it exists, but it is far too niche to be worth the effort.
How so? You literally just open a web page, and choose a nickname. It's easier than creating a Discord account and verifying your email address and phone number.
Discord has a gradual onboarding process. If your IP isn't poisoned, and your browser looks pretty normal, you just have to enter a username and you're in with an "unclaimed account"
They'll then nag you to fill in more details as you use it. It's honestly a pretty slick way of doing onboarding.