When you say you find it a waste, you are either saying:
a) There is a less resource intensive way of doing bitcoin
b) That the claimed benefits are not true or you don't value it
(a) has had plenty of tries without success.
In case of (b), you don't have to participate, it's an entirely voluntary system. There are plenty of energy use cases around the world which don't benefit everyone.
You say "you don't find valuable". Its not just me. People, in general, don't find cryptocurrency valuable. Nothing backs them up, and besides that you cannot widely use them in the clearnet/sneakernet.
What happened is it hasn't replaced the default currencies such as USD and EUR. Its been mainly adopted by criminals/crooks (e.g. drugs trafficking), tax evaders, people who live in banana republics (hyperinflation), speculators, and a bunch of libertarians/preppers.
So next time you say "you don't find it valuable", please realize you're talking to the vast majority of honest, casual people in the world. Of the above mentioned groups, the _only_ group I have respect for using cryptocurrency, is the people who live in banana republics (such as Venezuela).
I highly recommend this piece (which I'm paraphrasing here) if you're interested in the topic:
https://unchained-capital.com/blog/bitcoin-does-not-waste-en...
I'd say every bank teller in the USA driving to work every day is a total waste of energy.
But yet it all seems necessary to build trust. Is it proof of work?