You know - not that I'm professional - I really do get turned off by animal decks. I find them entirely fake. What do Llewellyn know about whether an animal has a soul?
A) Llewellyn is just a publisher, not the actual artists of the decks. They're in the business of publishing what sells to a specific market, not solving the existential animal-soul/no-soul crises.
B) They probably know as much about animal souls as we know about animal souls.... or tree souls... or people souls....
What's Disney got to do with how people perceive animals? I'm pretty sure there is a long storied history of people identifying with animals eons before Disney was even a person and definitely before their IP nightmare of an empire.
I honestly don't see how any animal deck can be convincing. I love animals, deeply, from the bottom of my heart -perhaps more than human beings - but I don't think the world needs animal tarot decks because we just don't know the essence of animals. It is all romantic imaginings, overly sentimental, investing human feelings, investing human emotions, inventing profundity, pretending we are at one with nature when the fact is, we know nothing.
Discounting thousands of years of anecdotal evidence as hearsay; Centuries of peer reviewed biological research, especially the strides made in animal behavior in recent decades would disagree with you on the amount humans know about animals, their emotions, and their behavior both domestic and in the wild.
Also, as applied to tarot, you need the deck you need. Furthering your ecological argument below, technically the world needs no tarot decks, like, at all, but tarot is the least of the worlds problems. Some people, however, do need animal decks to connect and make sense of their tarot/spiritual practice. You have no idea how each person applies the animal symbolism and energy to their practice, and as such, you're hardly in a position to decide what is or isn't needed for that person or the collective world for that matter. Just because you don't connect with a particular style deck, doesn't mean others don't.
If we loved nature, we'd stop buying shrink-wrapped decks and manufactured crystals and just shopping less.
If we loved nature we'd do a lot more than shopping less and ceasing deck collecting, but that's another discussion for another time.
But - hey - that's just me. I find them totally insincere. People can like them and feel free to like them of course - but what do I think? Fake and invented. At least - if you're going to design a deck - invent about human beings for which you have some level of familiarity. I have no doubt that the fluffiness appeals to clients but I don't think they're doing much to further our understanding of the natural world.
Your premise of people being familiar with people is inherently flawed. If that was true, the world would be a lot nicer, and we wouldn't need tarot. At all. The whole point of tarot is to gain an understanding of the world around you and the people in it, with like 99% of that being human interaction.
Animal themed tarot isn't for understanding the natural world, it's for understanding the human world, using animal themes as parables for human behavior.
Also, not all animal decks are fluffy, so... there's that. That's like saying all human decks are just full of sweaty glamour models.