> copy things into different structs all over the place Sanitizing input is a very common pattern and I don't see why this option is such a deal breaker. And i

> copy things into different structs all over the place Sanitizing input is a very common pattern and I don't see why this option is such a deal breaker. And it would normally just be needed at the system boundary, rather than "all over the place". Or, you share types between different services using something like grpc or thrift, and then you really can trust that the values coming in are not going to be null. I definitely don't agree that settling for implicit null is the best option.