Sure, the problem is hard. But so are most problems worth solving. That it's hard doesn't mean it's impossible or excuse bad solutions; Direct3D actually does an extremely good job at it, in fact.

If you've not used modern Direct3D, it's hard to concisely explain how much better it solves this problem than OpenGL. It's just a cleaner, more elegant, faster API (of course, I know this wasn't always the case, but we're talking about now).

Many of the "non-game" problems you mention really have nothing to do with the API and should be solved by third party libraries or the OS. Text rendering is not a GPU feature so don't expect a graphics API to treat it as such. The problems game developers find in a 3D API affect everyone, because at its core the 3D API is just our way of talking to the GPU.

The main complaints from "non-game" applications like this are either common to everyone (texture, render target limits), or application specific things that have absolutely nothing to do with the GPU (like text rendering) and have no place in a low level GPU API.

I know it would make your life easier if the API was more like a library with exactly your use cases already implemented, but that's simply not the role of a hardware API.

P.S. You probably shouldn't be using polygons for font rendering. Nobody does it this way in practice (except rare cases perhaps). But this is another discussion; feel free to message me privately and I'd be glad to provide more info on best practices.