> as measured by the number of people who can do it

That’s a poor measure. It proves only that there’s a demand for such programming. I have programmed in tens of languages professionally and many more for fun.

Programming is programming. I haven’t found much difference in difficulty between any of the stacks I’ve worked with. Except, maybe C++, but that’s just C++ being garbage. I now happily use Zig as an alternative, and it’s no more difficult— easier in fact— than building a well-architected, complex UI application of any kind.