So to recap, this thread has three people posting in it. One person is claiming this is affecting EVERYTHING EVERYWHERE THE ENTIRE WORLD HYPERBOLE
The other person is asking for specifics, which boss, which ability.
The final person ignores the person asking for specifics and agrees that pets are more fragile.
Just to cut to the chase here, this is not in any way helping your case. Provide specifics or you are no better than hysterics.
Are you trolling?
There does appear to be an issue with AoE and pets. I noticed it on my hunter as well.
To say that this is intended, even if you only mean for rares, is pretty baseless;
1. Bliz never said they intended it.
2. There is nothing in the patch notes about this change.
3. It does not make any sense with respect to the basic reasoning behind giving pets avoidance in the first place.
Before late LK pets could be controlled fast enough to keep them up when bosses AoEd. Bliz did not implement many fights with extremely punishing AoE damage and there was less AoE overall in PVE.
However, Bliz began making AoE a big part of boss mechanics, they also made the expectation of player reaction time to AoE higher. We simply needed to get out of the fire more often, in more varied ways, and with less time.
They had the choice of buffing pets so they had healthpools, damage mitigation, armor, and avoidance mechanics similar to players so hunters could be expected to REACT and save their pet in the similar time it would take for any player to react and save themselves.
Making hunter pets that powerful (and that controllable) would be game breaking outside of raids.
It was also at a time where they were trying to reduce the number of things hunters had to manage and the number of buttons they needed to deal with (hunters currently have 11 buttons in their priority rotation not including on use trinkets/enchants, not including pet management/healing, and not including traps/utility/misdirection or not including defensive cooldowns - in the past it hovered between 14 and 17 buttons).
Ultimately giving pets AoE avoidance was the most elegant solution. It also did little to "buff" hunters.
To expect hunters to have more than 33% faster reaction times than players while controlling their pets is not reasonable - even for rare mobs. Not to mention all the control functions for they would have to add to the game to deal with current more precise AoE mechanics.