I don't do baby talk because I just don't like it. Not to babies not to animals.
I do find baby talk irritating, but to each their own. As long as they don't say anything to me for no baby talking I won't say anything for those who baby talk.
But I will just say that I'm under the impression that baby talk is done more for the talker wanting to talk like that, rather that for the listener to have a easier understanding, as I was always understood the same without baby talking and just trying to use simpler words for smaller kids but without that cartoon voice.
I don't either and I can say from my experience my nieces and nephews thought I was mean when they were little because everyone else did talk to them in baby voice. I even asked their parents if I had done something to scare them or hurt their feelings and they couldn't think of anything and I was never around without their parents there. They grew out of it but it kind of sucked for a while.