Energy is the key driver of productivity in this world. Now, energy costs money, which incentivizes people to try to use it efficiently to achieve whatever their goal or whatever it is they’re trying to produce.
The question isn’t quite “should we worry about power consumption” because the market already does that pretty efficiently. Generally speaking people will try not to just throw away money if they can think of a better way to spend it.
So let’s assume we’re not talking about eliminating pure waste, because that’s an obvious answer. There are a lot of companies that focus on identifying and eliminating energy waste actually.
But I think what you’re asking is, to what extend should we actually limit marginally productive uses of energy in order to reduce overall consumption, even when the value of the end-product exceeds the cost of the energy?
My personal answer to that is… not at all. In fact, I think energy is way too expensive overall currently, and we need to be working very hard as a society to drive down the cost of energy, and in turn, increase per-capita energy usage significantly.
Energy usage is directly correlated with standard of living, health, and economic output / productivity. Increasing energy costs or throttling energy usage is a regressive tax and ultimately stymies economic growth.
I would guess that the next great human accomplishments in my lifetime will be a human on Mars, abundant clean energy on Earth, and cheap/practical immunotherapy to cure cancer and auto-immune diseases at low cost.
I doubt it will be quite a “Mr. Fusion” on the Tesla I can toss breakfast scraps into and then drive 300 miles, but for example, solar panels and battery system efficient and cheap enough to give me all the energy I could need for something on the order of $1-$2 a day (current electric bill is more like $12-$15 / day).