> - object initialisers

Probably not a good idea since they break encapsulation by exposing internals of the class. There is work on withers, which should make defining builders far simpler.

> - extension methods.

They make code harder to understand. If they ever come they would have to be declared at the top of each source file.

> - null coalescing operator

Maybe we'll get it, maybe not, but they want to first introduce proper nullable types, lest there is a risk of painting themselves into a corner.

> - async/await

There is a fork in the road, and Java has gone into the direction that leads to virtual threads and Structured Concurrency, for the simple reason that there is no simpler syntax than plain old synchronous code.

> - ... generics metadata in runtime

There are plans to add a kind of reified generics, so maybe we'll get it.