There is a significant amount of research from the field of computer vision before ML even existed. It was quite robust as well within certain constraints. Those techniques simply did not generalize anywhere even close to as well as deep learning.

However, that said, in a tightly controlled environment such as a manufacturing line trying to spot defects I would imagine they would have a good chance at performing a lot better than deep learning.

A lot of the advancements in deep learning have also come out of ideas from that research. While they didn't use the techniques directly, there is a lot of knowledge that we'd be lost without.

This is one thing that scares me about ML. We are losing research into the fundamental physics/science to deeply understand these things and instead just throwing models at them.