So are the level 82 mobs in Vashj'ir
Anyway I logged in and checked and I really am wrong it's 9 level not 10. There's actually a list for the levels mobs stay green, it's depending on your level so it's very likely it'll stay 9 levels in WoD too.
Level 1-9: 4 levels lower
Level 10-19: 5 levels lower
Level 20-29: 6 levels lower
Level 30-39: 7 levels lower
Level 40-90: 8 levels lower
On the downside I rode around Deepholm for a bit and aggro ranges even for lvl 82 mobs are not quite pitifully small. And yes they can daze and dismount you, I checked.
I'll be curious to see if you still feel that way 15 months in the expansion after you've wasted "about 10 seconds" a few hundred or thousand times.