Canelo is not the huge draw people want to think he is. Nobody outside the Southern states has even heard of him.
Because that is where HBO, and SHO, distribute the ppv. The mechanisms(customers ordering, show delivered, billing, etc) have probably not been set up for them to do ppv internationally. It's complicated enough for them to do it in US(and possibly some parts of Canada). That's my guess.
Maybe dollar wise. But not number of ppv buys. Times are just different from then. Times are harder. Boxing not as popular. People have other things they would rather spend on. That 2.5 million is gonna be awfully hard to reach again.
Oscar was more known than canelo. Floyd only got around 350k ppv before he fought DLH And I'm sure canelo can't pull anything near that. So around 1.5m would be good guess