During installation HomePod's reach out to validate they are running the latest version as required by the iOS device you are setting them up with, and they do

During installation HomePod's reach out to validate they are running the latest version as required by the iOS device you are setting them up with, and they do all kinds of connectivity checks cause they don't work on captive portal networks either. I am betting one of those checks fails because its on a network that blocks port 80.