Is this likely to become a problem for the IC now or In the future ?
1st is ETH
2nd is BTC
I think this is unique to Ethereum’s PoS consensus model.
IIUC, the majority of Ethereum blocks are OFAC-compliant because they are proposed by MEV (maximal extractable value) relays that enforce censorship, e.g. Flashbots ignores transactions from the recently sanctioned Tornado Cash service. Validators often opt to use centralized MEV relays to maximize profit.
This problem doesn’t happen on the IC, as blocks are produced through a completely different consensus algorithm. The relevant difference is that IC nodes are permissioned by the NNS; in other words, only the 13 nodes in a typical application subnet can propose blocks. Nobody else can. There is no need for MEV relays; there is no profit motive as there is no reward for validating blocks (nodes are rewarded based on uptime). As a result, blocks cannot censor transactions from Tornado Cash (or Spinner Cash), at least not in the way that Ethereum blocks do.