Any large client bug can create quite the headache for Ethereum stakeholders, but the bug is amplified if a large portion of the nodes are all experiencing the same issue, potentially tricking the chain into believing their bugged chain is correct. An issue like this happening with two-thirds of nodes could lead to a chain split, creating larger security risk for users and developers, slashing issues for validators and potentially needing a bailout from the overall network, which is inherently not a very decentralized solution.
Ethereum Is Only as Strong as Its Weakest Link — CoinDesk
