vCenter 7.0, Lifecycle Manager fails downloading depot metadata & proxy

Recently I’ve seen more cases where the Lifecycle Manager in vCenter 7 fails syncing updates and pulling depot metadata. In this case you see an error like: An error occurred while downloading depot metadata from https://hostupdate.vmware.com/software/VUM/PRODUCTION/addon-main/vmw-depot-index.xml.. Just to note, the usual disclaimer:...