We currently have an iPad Pro that serves as the main HomeKit hub, with an Apple TV as the secondary. There are always certain accessories that show no answer and kill me. I think we should switch to the Apple TV main to solve unanswered problems, but my son is firm that the iPad is fine, being the main. I disagree.
I also have 3 lamp sockets in the living room. How is it possible that only one of them shows no answer? It is not always the same socket, but it changes randomly. Same experience with wemo and meross stores. It’s driving me crazy.