I never said it was. Given their track record, I'd trust Blizzard with esports just as much as I'd trust a toddler with a pistol.
That said, the first Dota TI was played at Gamescom to like dozens of people, & now TI boasts $30m+ prizepools & viewership second only to League outside of China. Of course I'm not saying I think WoW will get anywhere near that big (or that it'll grow much bigger than it currently is), but Blizzard could 100% step in & possibly make it better, or, more likely, make it worse. Not a salty Starcraft/WC3 fan, by the way...
Easiest & best thing Blizzard could do at little to no expense is global release. Side by side views of guilds progressing the same boss at the same time with similar farm time leading up to it would be pretty cool
I've no idea about all that nationalistic stuff regarding WoW, but I can probably put a picture together from having watched other esports.