The physics curriculum prepares people to do research on stuff that is published in "physics journals". You may not think that should be the goal but it is. Doing work on Navier-Stokes lands you in a math journal on PDEs.
On a more important note, the actual topics are completely irrelevant. What's important is learning to "think like a physicist". That's what has value even for those who don't go on to do academic research, which is most students. For any given physics topic that is relevant to real-life applications, there are engineers who actually know how to use it, something that would be ridiculous to expect from the superficial treatment a physics degree has to give any one topic.
Fitting and customizing things takes time and is expensive. That fully explains the trend. Before industrialized mass production, making an item by hand and to fit someone's specific needs was only slightly more effort than to make some "average" fit item.
What do you mean?