If that were the case they would have faced him at 135. Pac is not Zahir Raheem at all. And Morales barely lost to Diaz if at all. I actually had Erik winning that fight by a round but Diaz prolly did outwork, I'll have to watch again.
Well Pac didn't move up to 135 until almost 2 years later so maybe 130 was just Pac's weight class at the time, he was the champ, and Morales wanted the rematch and the belt. Pac went on to have 3 more fights at 130 including ones with Marquez and Barrera. That's pretty impressive, actually.