That's easier said than done. There are tradeoffs on expressive type systems too. That being said I wouldn't mind more expressivity in the Go type system. I'm actually looking to implement my own small features(i.e optionals, variant types) in a Go superset.

Where do you think struct tags fit in all this ? do you really think go designers took the time to consider the tradeoffs of such feature ? I don't think so.

Any sufficiently advanced type system is indistinguishable from magic.

But putting struct tags in Go was a good idea that promote simplicity ... I prefer the magic of generics or pattern matching or covariance to insane features like this, thank you.