Comparing BTC to beef is the wrong comparison: we should be comparing BTC to USD. Over 95% of the USD money supply exists in digital form only; while there's no proof-of-work element to creating new USD the electricity to run all of the servers at all of the banks, Federal Reserve, Treasury department, etc is non-trivial. The physical protection of the money supply (Secret Service, FBI) also has massive cost and impact. And the ultimate environmental impact is the "full faith and credit" of the united States governement -- which translates to the US military-industrial complex and the threat of force of arms -- which causes far more environmental damage.
(And yes, we do use our military to protect the USD: we killed two heads of state primarily because they wanted to price their oil in something other than USD. Had they succeeded that would have killed the petrodollar system.)
(And yes, we do use our military to protect the USD: we killed two heads of state primarily because they wanted to price their oil in something other than USD. Had they succeeded that would have killed the petrodollar system.)