I can imagine people honestly believing that. So many jobs today are utter bullshit, and so many more are enough layers of abstraction away from anything useful than it's hard to find any motivation other than paycheck. And there are many people who would like to feel they're contributing to something, not just selling their time for currency.
I think this view is very wrong. Lots of people take pride in the fact that they're doing some socially valuable job. That might not be their primary motivation but it's an important one.
A lot of people get into jobs to help people, or help society. But to help "the economy"? I'm skeptical (in the sense of doing a day job because markets need it, not a job that's making the economy as a whole more efficient). If the market doesn't pay for a job, then "the economy" doesn't need that job.
Most of those are in the service, police, fire, or rescue. being a delivery driver (pilots are a form) and making such statements is just an odd romanticism or at least a bad attempt at making the job seem more important than it is.
You're confusing fungibility for importance. While one particular delivery driver or pilot may be less important than one particular "rockstar programmer," society is much more reliant on delivery drivers and pilots as a group than on programmers. That may change with automation but we're not there yet.
