Great question that really got me thinking. De la Hoya travelled through 6 weight divisions and faced the iron in most of them, so he edges it in terms of numbers of Hall of Famers fought. Holyfield went into fights more often giving away physical advantages against elite guys though.
Yes, De La Hoya had the pick of the opponents from 130 to 160; Evander was a novice Light Heavy, who moved up and cleaned up a mediocre Cruiserweight division, but then could only fight fellow Heavies, when he got there. Holyfield did indeed fight virtually everyone that mattered in the division in the 90s, but the quality was, understandably, often below what De La Hoya was fighting.