There is a 1 or more second delay between commanding your pet to attack, follow or passive which causes inherent problems with other features such as feign death, pet abilities, pulling/kiting mobs, etc. It’s almost as if everything the pet does isn’t recognized in the game until after the delay. Even their position in the game world.
Pets are supposed to respond immediately to commands without delay. Thus, a hunter should be able to put pet on passive and immediately feign death to get out of combat and put up a trap before another attack can be made on them or their pet (unless in PVP a warrior taunts your pet precisely at the same moment you feigned).
The delay also causes problems with aggro range. Pet aggro range should be the same as a player of the same level as the pet. However, right now you can send your pet literally right up to any mob, and then pull it back without ever aggroing the mob. It needs to be in that aggro range for more than 1 second to aggro the mob. This makes it much more difficult to send your pet out to gather a mob or a bunch of mobs and bring them to you without your pet taking much initial damage or even without pulling other unlinked mobs unintentionally. If you want to do this now you have to pre-empt the delay, which is near impossible to do consistently.
I noticed a blue post that stated “Pet aggro radius is working properly and as expected. This is to say, it was extremely inconsistent in original WoW, and it remains inconsistent in WoW Classic”. I played beast master hunter all through Draenor and for the first few months of Legion and never had any pet delays or inconsistency with pet aggro radius. There was especially never a time where the aggro radius was zero. Due to the delay, you can literally send your pet 1 yard away from a mob and have it return to you without aggroing. You can do this consistently. That should never happen. Should the delay be fixed, you will find that the pet aggro radius is pretty consistent and most other related problems will disappear.
This delay probably also accounts for why pets do not attack NPCs from behind when they start running toward you, after you’ve generated more threat than your pet. Instead, it appears almost as if they are strafing sideways.
Same delay probably accounts for why it seems like pets aren’t casting their abilities on time.
In summary, the entire game is delayed in recognizing pet commands, abilities and even the pets location in the game world. This severely gimps hunters and warlocks.
I noticed this problem first when I re-subbed BFA a few months before classic. I played the original Vanilla and every expansion through Legion and quit about 3 months into legion. There was never a pet delay until I re-subbed to BFA. It is definitely game breaking.