I completely agree with this. Years ago there was a book (Umberto Eco's Travels in Hyperreality for anyone reading at home) that discussed how the Disney parks, through technology, try to provide more reality than nature can. If you go down the Nile or
Amazon, you're not going to see crocodiles, hippos, elephants, and all sorts of other things - you may walk away disappointed that you didn't see anything at all. Disney, however, can give you all of that on a 10 minute jungle cruise or safari trek. Disney has never tried to just imitate reality, but improve upon it to make it bigger, brighter and more entertaining than what you'd find in everyday life.
In that sense, I have no problems with the Beastly Kingdom (or Pandora) or anything similar. Disney isn't the San Diego Zoo or National Zoo - those places would be rightly criticized for using their money to build an imaginary creatures exhibit instead of focusing on their real, live animals. AK, however, is not and never has been just a zoo. They have the benefit of being both a zoo AND an amusement park. And they should take full advantage of that.
All that said, the animals are the core of the park (it's right there in the name- "Animal Kingdom") and should stay there. It's also the park most grounded in reality - real animals and not just animatronics. I think that's why it's one of my favorites. Disney has had to blend that reality with all of its "better than reality" Imagineering and world building - and they've done an impressive job of that. A fair criticism of Pandora and IJ is that those lands move away from the real animals at the heart of AK. I'm not against those lands outright (or Beastly Kingdom) - but do think that they should complement the zoological features of AK rather than pushing them into the background.