Go could do something similar if you're willing to run `go generate` as part of your build process. For most Go applications, the reflection overhead is a fine price to pay for convenience, just like GC is a fine price to pay for not having to deal with the borrow checker. Obviously, these tradeoffs don't hold for all programs, but Go has definitely found a niche.
I'm not sure what you're arguing with. I know these things. I'm still missing the ability to have efficient serialization (as one example) easily. It matters.
I’m not arguing. I was just highlighting that you could easily implement a json library that uses go generate instead of reflection. I was positing that such a library hadn’t been made yet because the perf hit of reflection is fine for most people. Also, just an aside, if perf is a concern than JSON isn’t a good choice to begin with.