In Ethereum's case, it's not green washing, they're already halfway to implementation. The proof of stake chain is live. The proof of work chain will be merged

In Ethereum's case, it's not green washing, they're already halfway to implementation. The proof of stake chain is live. The proof of work chain will be merged into the proof of stake chain in the next six months: https://ethmerge.com/ https://ethmerge.com/ Clearly with hundreds of billions in economic activity on the POW chain they have to take this very carefully.