Miners pay for the electricity they consume and from purely economic point of view it's okay but not so as far as efficiency is concerned.
I have seen many known bitcoiners who are considered oracles that have made the wrong arguments concerning proof of work's wasteful use of a limited resource.
Some of their arguments are bitcoin is pushing for the use of renewable energy. What? If there was one that matters then please tell us about it.
Another argument is but the banking system uses more electricity. Ok turn off the whole banking system now. Let us see if bitcoin can handle everything.
Very stupid arguments from supposed to be smart people.
Wasting what? Answer: their own money. What makes you think you can tell others what to do with their own money? It's not affecting you, you have no cause for complaint.
The pair of you have not gone to the trouble of finding out why proof of work is used in Bitcoin. Don't be surprised if there's little sympathy for your ill-informed views.
Read this sentence:
Bitcoin Proof of Work is providing a valuable service. More is better. See if you can figure out why that's true before you waste everyone's time again (ironically, you wasting everyone's time is a waste that is affecting other people)