MechE here so my thoughts can be biased. It’s high because of two reasons. One the pay is typically much better (upward of 20%-100% (yes 100) better) and secondly the “crossover” barrier is much lower compared to other engineer mobility. For instance I would argue, a MechE becoming a SWE is easier than a SWE to become a MechE since companies are opened to SWE not having a specific degree in it.
I wonder if there might be a technological barrier. My degree is in physics, so I depend on mobility for any hope of employment. ;-)
It was easy to learn programming. One reason was that the tools were always relatively cheap (even when they cost money), and the cost to learn by trial and error was negligible. At least this is true for the basics. Becoming a good programmer who can be an asset to a large project is outside my wheel house, though I'm in the process of learning.
Today, for mechanical design, you at least need access to SolidWorks, and the part of learning that comes from experiencing failure is costly and time consuming. Surely 3d printing is changing that equation, but not overnight.
But you can test the waters of programming without asking anybody for permission, and if you discover that you hate it, then you can just bury it. And many do. Programming is hard or most people, for reasons that I don't think we understand.
Now, programming and mechanical design by themselves are not engineering, but if someone wants to get into a new skill through the back door, they are similar. A person with SolidWorks skills can be useful as a designer without being a full blown engineer.
