Ethereum

Are validators in the same cluster (eg same exchange, same user) more likely than unrelated validators to miss attestations at the same time? If so, can we tweak rewards to favor decentralized staking?

Possibly yes.

https://ethresear.ch/t/supporting-decentralized-staking-through-more-anti-correlation-incentives/19116

This doesn't make sense to me but I'm not very smart.

Savvy operators will spread across multiple locations.

Less savvy home stakers who happen to run handfuls to hundreds of validators will be unfairly punished.

Basically disincentives home stakers.