Fair enough, perhaps I exaggerated a bit, but he isn't very good. Accent has nothing to do with it Eddie Guerrero had one and was brilliant. A baby with down syndrome is better on the mic than Swagger, so I'm not going to give him a ton of credit for that.
Punk, Barrett, Heyman, Henry, Coulter, Kane, Bryan, Rock, O'Neil, Show, Miz, Jericho, Rhodes, Ziggler, Ambrose, and Rollins are all better. That's just off the top of my head.
Rollins? I'm starting to think you've actually never heard Del Rio speak at this point.
Some of those are very arguable as well. He's easily better than Ziggler, Rhodes, Titus and Kane, but Rollins? Just no. Not even on his worst day.
Heyman and Colter aren't wrestlers (well, Colter's retired) either, so they shouldn't even count. Obviously Heyman is unfair to compare with virtually anyone regardless, though, it's fucking Heyman.