Should this mention "why" someone might want to do this? I.e. I think the relationship to decorators? Not that those are very documented, either.

Ah.. Right! Perhaps simply: less boiler plate code? This is exactly what is visible in the examples. Or?

Well, the immediate question with this example would be "if it generates me a getter and a setter, why not use a prop"? So I would figure that there's some other reason for them.

why not use a prop

A prop is not a readonly field.

Of course, do I understand this isn’t a real world example. The aim is slightly different. Last week I saw the accessor keyword and I did not know what it is. Let’s read the docs, is the first thought. But there was nothing about that.

On second thought, this indeed sounds mostly useful in decorators context. So leaving it for the future.