Is there a possibility a peer are unable to take a message from other peers among Gossip sub-network

I read the relevant paper that says the gossip is emitted to random subsets of peers that are currently not part of the mesh. Take an example. If there were up to over 6,000,000 peers in a gossip sub-network, each of peers is unable to link all the rest of peers in the same gossip sub-network. In some cases, I guess there should be a peer that is unable to take a message from other peers as it is being isolated. Is that right?