The kind of person who is useful in engineering is that person who gets to the bottom of things. They not only find a way to understand the problem, they also find a robust solution. You come across this kind of thing on HN often, like that article about the guy who opens safes with a device hidden in a marker pen. For 99% of people, that level of effort is incomprehensibly deep. I mean you really have to know a heck of a lot about the subject, and you have to be willing to hurdle quite a lot of issues in the solution as well.
Math is the ultimate get-to-the-bottom-of-things subject. That kid who asks you to explain Euler's identity, who wants to know why only 23 people are needed for half of such groups to share a common birthday, and wonders whether there's something deeper than complex numbers when looking at polynomials. The kid who diligently expands his binomials just to see that the formula is actually right.
That kid is also the one who will figure out why your rocket is malfunctioning, how your car will drive itself, how to fix carbon dioxide, and every other problem that we call a technical problem.
So yes, you don't need advanced math to do a lot of these things, and maybe doing advanced math doesn't even help you do these things. But math is a sort of flag that suggests you can get to the bottom of whatever problem you're faced with.