&gt; Even worse, proof of work is almost exponentially getting worse over time.<p>Huh?  Exponentially?  The difficulty level is rising exponentially, but that&#x27;s owing to continued investment in specialized hashing hardware.  I certainly don&#x27;t think that the actual amount of electricity being put into hashing is still growing exponentially.  It would only grow exponentially if the price of Bitcoin continued to appreciate exponentially, and that hasn&#x27;t been the case in years.