It was very popular all across Asia too, except maybe China where Internet restrictions probably led to local competitors,sprouting up. It likely wasn't popular in the US as AOL captured the market first, and the impact of network effects is huge when it comes to chat apps.
Interestingly, MSN Messenger's capabilities in the late 90s/early 2000s were quite impressive. I remember being able to make long-distance audio VOIP calls using Messenger back in 2000, even on an awful 33.6kbps modem. The feature was removed pretty soon after, probably because it was abused (there was no charge for calls).
You could also send decently sized files (~10MB) using Messenger until about 2005, and that too was discontinued as people used it to send MP3s to one another.
