It's not magical, granted. "The economy" is a subjective state (eg metrics) that solely resides in the human mind, rather than a singular thing.
It most certainly is and I have not encountered anything to indicate otherwise. Individual transactions are no more relevant than GDP is. These are individual metrics or acts that influence those metrics, which try to quantify aspects of an aggregate concept.
I would frame it with a different emphasis. Want is inherent to living organisms, humans and others alike. The economy discovers, amplifies, and satisfies our wants. But it is also important to remember that economies emergent, not some external object imposed on humans.
Is that an issue? There's not much demand for 8k ohm SMD resistors from people, but people do want smartphones that require 8k ohm SMD resistors to manufacture. The same applies for stuff like managers and other "bullshit jobs". Nobody wants them, but they're nonetheless required to keep the company/economy humming along. And if they're actually not required, then the economy that supposedly cares what's "economically most efficient" should have eliminated them.
There is a mountain of trash end-products out there, which marketing is creating the want for. These products may not otherwise exist without the manufactured want, and could be removed entirely without much detriment to the very small amount of people that conscientiously decided of their own free will they wanted that product.
Marketing is what makes something like a Peloton a viable business, rather than those customers just taking a regular static bike and adding a tablet mount to the handlebars.
In some senses, I think the economy isn't always looking for the most efficient methods. I believe there is some political input involved to keep everybody's heads down under a quagmire of pointless work, so those people (even in a democracy) don't start asking too many questions. Some people could easily be automated out of work, yet they aren't, despite the efficiency it would bring.
To each their own, but I'd be fine with a huge amount of (what I deem) useless products and jobs being removed from the market. Most serve very little real purpose and as somebody else stated, are destroying our planet and wasting away the best years of our lives to attain them.
One of the best known examples is the PR-manufactured tradition of diamonds in engagement rings, which sky-rocketed the demand for diamonds in the general population.
Another great example is the huge industry of "supplements" which is legalized fraud on a massive scale, selling useless pills to people with a promise of making them better in some way, and relying solely on the fact that it's hard to prove that they don't actually do anything since their claims are so vague.
These are prime examples of entirely artificial demand created out of whole cloth through manipulation. There are numerous other cases of more subtle effects, where marketing is significantly inflating a demand which would exist but be much smaller otherwise (toys, smartphone upgrades, new cars every few years, beauty products, fashion etc).
Obviously this cannot be true. "The economy" isn't some magical object somewhere, but the emergent behavior from all our needs, desires and faults. If something is truly not wanted by anyone, nobody will pay for the work to get done. That's the magic of the invisible hand of capitalism. Doing stuff that truly nobody wants and getting paid for it is usually more of a feature of socialism and bureaucracies.
There are cases where individual motive leads to macro behavior that's not desirable by any individual, those are the cases where we need to tax negative externalities or regulate, depending on the problem. These issues usually don't emerge though because nobody wants something but because too many wanting a thing creates side effects that nobody likes. The book Micromotived and Macro behavior by Thomas Schelling covers that nicely.