I’m not sure publicly criticizing and agent is good way to get an agent. Better to maybe reflect on your own experience and the rejection, any advice that was given and leave it at that.
Rejection always stings a bit. It is your precious they are talking about after all. But no point in getting angry. Because it can take many agents before you find the right one who will take you on, or so I heard. And you want someone who enjoys your work and wants to work with you. Worth waiting for really.