Except that the study has two giant flaws.
First, MMA is grouped together with pro wrestling (or "lucha libre" south of the border). This would be like grouping cricket with baseball (they both have sticks and balls!), and then declaring that cricket has penetrated the U.S. market. Pro wrestling, like here in the States or over in Japan, has deep cultural roots in Mexico. It's no surprise that first- or second-generation immigrants would maintain ties to it.
Speaking of sports with cultural ties, the study seemingly left boxing out of the study. Saul Alvarez drew 36 million viewers in Mexico last month for his fight with little-known Ryan Rhodes. Julio Cesar Chavez Jr. brought in the highest Boxing After Dark ratings in 4 years (about 1.5 million viewers) opposite Sebastian Zbik. Oscar de la Hoya holds the pay-per-view record with Floyd Mayweather Jr. with 2.4 million buys in 2007. Boxing is big business in the Hispanic market. Its exclusion is a glaring oversight.
I'm not sure where MMA would stand without the tie to lucha libre and with boxing's inclusion. I feel it would fall behind a top 5 of soccer, boxing, luche libre, the NFL, and MLB. MMA, specifically the grappling component, does not hold any cultural significance in Mexico, and the sport contains no legitimate Mexican stars despite the success of multi-cultural fighters like Cain Velasquez, Tito Ortiz, and Dominick Cruz.