I've been looking at past The Ring ratings on Boxrec, and I kind of wish this fight happened. Both Lopez and Wonjongkam were long-reigning fighters who fought at lower weight classes. Who would have won if Lopez moved up to fight Wonjongkam?
Two different eras. Wonjongkam became champion in 2001, the same year where Lopez retired at age 35. You can criticize Lopez for missing a lot of notable fighters but this is not one of those cases.
Beating Wonjongkam would have been a nice feather in Lopez's cap, assuming Wonjongkam still goes on to have a long reign. Lopez was a GREAT fighter, but he could have done so much more. Instead, he chose to sit on his WBC belt and fight lesser fighters.