[gthrowaway52]

> Just take a step back and think about what you're saying: that a bitcoin transaction would cost £3.40 in the UK

I hope I'm not misinterpreting your point, but bitcoin transactions cost even more than that.

https://ycharts.com/indicators/bitcoin_average_transaction_f...

Users have to bid for space on the blockchain to store transactions. Early on the space was cheap and miners got their profits from the # of bitcoins they mined. As that dries up the incentive to mine shifts toward transaction fees.

The electricity costs right now are unclear to users because of indirection. Mining dilutes the value of bitcoins each user holds but they do not see a loss in their wallet. I wonder if once confronted with even greater transaction fees over time whether users will be willing to continue to pay up to use it. One has to cross their fingers that the demand stays high enough to sustain enough mining to prevent the from being taken over with 51% attack.