The perception of the PoA mechanism is that it foregoes decentralization. So, one could say that this model of consensus algorithm is just an effort to make centralized systems more efficient. While this makes PoA an attractive solution for large corporations with logistical needs, it does bring some hesitation - especially within the cryptocurrency scope. PoA systems do have a high throughput, but aspects of immutability come into question when things like censorship and blacklisting can be easily achieved.
Another common criticism is that the identities of PoA validators are visible to anyone. The argument against this is that only established players capable of holding this position would seek to become a validator (as a publicly known participant). Still, knowing the validators’ identities could potentially lead to third-party manipulation. For instance, if a competitor wants to disrupt a PoA-based network, he may try to influence public known validators to act dishonestly in order to compromise the system from within.