Yes. There are several BFT compliant conensus algorithms for both Proof of Work and Proof of Stake. Some of them, such as Bitcoin, are BFT compliant because it'

Yes. There are several BFT compliant conensus algorithms for both Proof of Work and Proof of Stake. Some of them, such as Bitcoin, are BFT compliant because it's economically infeasible to complete an attack. Ouroboros is BFT compliant up to n/2-1 bad actors https://eprint.iacr.org/2018/1049.pdf https://eprint.iacr.org/2018/1049.pdf Edit: This goes back a comment I made the other day about 'Blockchain == Down votes' on HN. Why would you down-vote OPs question?