It wouldn't though. If you've designed something like this before, you'd know a type assertion is required no matter what just because of how serialization work

It wouldn't though. If you've designed something like this before, you'd know a type assertion is required no matter what just because of how serialization works. If you have some example code that can convince it would be useful though, I'll happily agree, but the only place I see where it can be useful (perhaps a callback?) can already be solved by "reflect". So I don't see any benefit whatsoever.