This is a thought experiment:
hypothetical scenario, pretend our fictitious p2p network is in a vacuum and all peers are speaking over ipv4.
How would it affect peer diversity if each peer refused to add an other remote peer that shares any of its IP octets? Obviously ip6 would break this to an extent. What if there were other stipulations, for example where nodes will not peer-exchange with a peer that is under X latency, or sharing any octets, or under N number of hops, rejecting signs of being geo-proximal?
Kademlia, Tapestry and other p2p schemes don't really address this as much as one might hope to. I know the practice of maintaining node diversity/non-diversity is there in the industry, but it seems as a practice to have faded out when the last of the good malware and p2p devs retired.