The reaction should depend on the animal. If we’re talking familiar-sized pets then people should be attracted to, eg, cats and I think ravens. Though if we’re talking about animal companions then the only ranger I’ve yet played called a spider and those they do run from. Okay suppose any giant animal might be similarly disturbing. I think they also react this way to summoned undead.
I think there’s the basis of a cool mechanic here that has NPCs reacting to your pets, with the ability to use those reactions to, eg, help your character sneak around unnoticed. But the way it is implemented is OTT and actually causes lots of strange bugs. I know I sent a long list when I did my ranger run a while back.
Hopefully the more buggy implications will be addressed in the full release and NPCs’ reactions toned down, without totally losing this feature.