The break-even cost of BTC is highly deceptive, as in so many other calculations that don't factor anything other than direct generation costs. This becomes relatively moot, for instance, were the electricity mandated by the Bitcoin maintainers and mining pools to be sourced from the least environmentally-damaging and polluting systems- which might change the /GWH cost and resulting calcs, but would be far less deceptive by not excluding indirect energy costs.