The fallacy is that ONE person dominated a year, with no exceptions. 98 would have been Jay AND X.
I witnessed 98, as 12 year old, it was overwhelming. It was years before I could even play "Hard Knock Life" or "Can I Get A", they were played so much, every outlet, every station, everywhere. I can say DMX was right there with him. I had "Hard Knock Life Vol. 2" poster on my wall that year, everyone I knew had a copy of that album, just holding it, and seeing the dark blue cd will give me nostalgia.
Jay was an event every year he came out, until the mid 2000's, but I'd say 2001 was the other year where he was largely uncontested, except in the last month of the year.