It's a testament to how great Mexican boxing has been that a fighter like Lopez isn't in the top ten of all time great Mexican boxers..... Mexico's boxing history is that great.
He didn“t have any fundamental flaw, no. Maybe you can say that Alvarez gave him problems because of this or that but that could be reaching too much since we can say that about literally anyone. I think he was better than Olivares but Olivares faced better guys and beat better guys (and lost too) but you know....
I'd say his inside fighting skills was something he seemed to lack. He was more of a midrange fighter and was more comfortable with not staying in the pocket for too long. Definitely not at the level of Chavez, Olivares, or Zarate when it came to in-fighting skills.