> Handling JSON as a basics for language?

Yes, even Mark Reinhold admitted that in the last "Ask the Architects" interview.

>null restricted type will come with valhalla

Will they? It's been 10+ years of Valhalla. Why is a compiler construct even behind project Valhalla? Kotlin has showed you don't need it to do them.

> string templates had a try

Yes they were over engineered and they failed to deliver a basic feature.

> Java is not a small language that you can throw features around, they have to take into consideration final goal of it and decades of development.

Yes I agree, but it shouldn't take YEARS to ship anything. 11 years for a JSON api?! Come on.