I believe he's 30 but he's never taken a beat down, he doesn't fight as often as a lot of fighters and he started relatively late. The only bad thing I can think of that he does is he gets up to 150-160 between fights. Given these things how long do you think Guzman has left in his prime?
He is actually 32 (born 1976) going 33 but with very limited professional fights (28 fights). His weight problem stems from the fact that he is aging and could no longer fit the 122-130 division. While gaining weight, he also lost his power and his last KO was in 2004 against Agapito Sanchez (who incidentally was retired for already 2 years prior to that fight) at 122.
If he can't make weight comfortably, especially for the biggest fight of his life, young is not the first word that would come to my mind.
Guzman has all the tallent in the world but lacks a warrior heart! he's not made weight in the biggest oppertunity of his carrer despite on paper having every advantage on paper, he was due to fight scot harrison for scotts WBO belt a few years abo in a fight guzman would have absoultly killed harrison but it didn't happen not gonna say he's a fair weather fighter but he certainly lacks the mental game to be elite in my opinion