> If a research scientist doesn't know how their work is going to turn out, they're probably on the right track. If an engineer doesn't know how their work is going to turn out, they're probably on the wrong track.
Your view of engineering doesn't fit with my experience. Certain areas of engineering are quite conservative and take that approach, using primarily proven designs (e.g., structural mechanics, fire protection). Licensed professional engineers generally follow that pattern. But this is not characteristic of engineering as a whole.
E.g., a small side project of mine is a device I intend to get a patent on. I understand the physical mechanism (the science) behind the device but have only a vague idea of what the actual device itself will look like. It's going to take a fair amount of experimentation to figure that out. Experimentation and design are fairly closely linked in engineering, and this was emphasized in my education.
Add on top of that the engineers who basically just experiment with various poorly understood systems. I'm thinking in particular about the industries with chemical processes and chip fabrication here. They might not have any clear understanding at all at first about why certain changes have certain effects. Now, some of these engineers might not care and accept that something works without understanding why. But many of them will look into that.
> Non-STEM folks might have a hard time understanding either field, but they might also be less likely to assume that they already do.
You identify a real phenomena, but I don't think there's a reason to single out engineers here. My own experience with physicists is that they are typically overconfident about their own fluid dynamics knowledge, for instance.