There is lot of confusion about this. The answer is as follows.
We are no better than
them.
but
We are no better than
they are.
So when it finishes in a pronoun use the object pronoun
except when the pronoun is the subject of a clause then we use the subject pronoun.
I didn't use your sentences because they seemed a little strange and I wanted to be clear. I am not quite sure why you would think monkeys are better than humans. Using this structure suggests that there may be some reason to believe that they are better and that in some way it is surprising that they are not.