I use codegen for MobX annotations. I've settled for MobX for reactivity, so I can tolerate the slight clumsiness of the code generation. What is a little bit annoying is that code analysis and completion are off if the generated is not up to date.

I have decided to give Dart+Flutter a try a couple of months ago, and decided to switch. The pattern matching is excellent, I can finally manipulate data almost as easily as in Prolog! I also like that D+F forms a cohesive, batteries included whole.

Underrated quasijoke!

And the result will be frustrating, fuelling the received wisdom that structural editing is just a bad idea.
I am a huge fan of JetBrains MPS. But I don't use it that much lately. Guess what -- the reasons have nothing to do with it being a structural editor!

For example, someone might see text as limiting (I do), and invent a visual language. But that language will have some crazy pet semantics, and be visually really fancy, and the tutorial will be idiosyncratic.

I think one very big problem is related to the fact that what convinces people are not ideas but practical systems that embody them. To be practical, the system combines a selection of ideas in a specific way. If the specific system fails to succeed, people dismiss the ideas along with the system.