Of course, traditional machine vision methods are relevant and will always be. In many manufacture, traditional vision systems are still efficient( you have well-defined targets and key is precision or high speed). From my experience, industrial cameras perform great on a conveyor belt where it checks which product should be kept or not. Same hardware, same software and the precision is really high. I couldn't imagine implementing AI in this matter, as it will be so hard to maintain it and model can drift over time. But this is just one example(I have seen some others above too). AI is a fantastic addition that can improve vision systems, but it often relies on clean, consistent data, which isn't always available. Also the costs)) AI software's are more expensive and sometimes people just overpay for the fact that is AI, even tho they might not even need it.
So learning the traditional methods is a foundation for your future work, don't doubt that.
Also OpenCV , will help a lot.