It probably eventually wasn't deemed important enough for that phase. In 1999 when Comic Chat ended they pivoted to their completely proprietary MSN Messenger service instead, with a stronger focus on individual-to-individual. This came after ICQ (1996) and AIM (1997).

Apples and oranges.

MSN was aimed at, well AIM, to the point where AIM used protocol flaws to block MSN clients. And it doesn't track that they'd just abandon IRC considering it was a period of absolutely massive growth for the protocol. It's more likely there was no intent to EEE IRC.