I know this is probably specific to my use case only, but it would be mighty nice if I could instantiate an annotation class in common code. I’ve written an external reflection plugin and library, and have to use an awkward wrapper around annotation information because I can’t just instantiate the annotation class itself.

Doesn't look like language proposal, maybe #multiplatform is better place to ask. Could you also give little bit more information, what is "external reflection plugin"?

It's absolutely a language proposal. Right now, the language seems to specifically restrict instantiating instances of annotations.

Why do you need instance of annotation?

I see, I would rather discuss it with #serialization guys, maybe there is some workaround for such use cases