Can't say about china, but at least here in south america Champions League is a big deal. But I guess that has to do with our players being important on top teams
There was an article I read once saying that Premier league is popular in China thanks the idea that it is corruption free, unlike their own league. Their TV rights bring in £32million. But with a big population, our teams spent time and money on trying to make them fans.
With South America, it makes sense that the CL is big, it is where you get to see the biggest Argentine, Chilean, Brazilian and so on players actually playing against each other instead of in their own league against lesser teams. Yet for Premier League teams, there is so much more money for them in the Prem.