> Developers shouldn't expect themselves to be able to do good design work any more than designers should expect themselves to be able to make scalable, reliable, maintainable, production-ready code.

Reread that sentence. It does not say developers can't do good design work and it doesn't say that designers can't write good code: it says they shouldn't expect to simply be able to do it. Nobody should expect to be able to do anything non-trivial they haven't deliberately learned how to do. Unless you have evidence that most developers have done the years of learning it takes to become a competent interface designer, that's just not a controversial statement.

If you're going to continue trawl my comment for minutia to be aggrieved by instead of making any coherent counterargument, you're on your own.