Is JPlus likely to become a mainstream JVM language as a Java superset?

I’m currently working on a project called JPlus (GitHub: https://github.com/nieuwmijnleven/JPlus
) — a modern programming language that runs on the JVM and is designed as a superset of Java. The goal is to maintain full compatibility with Java (allowing existing Java code to run unchanged), while adding modern features like null safety, type inference, data classes/immutables, higher‑order functions, pattern matching, async/await style syntax, and a new apply syntax to reduce boilerplate (see the demo of the IntelliJ plugin here: https://www.youtube.com/watch?v=0z_aIyBpJso
).

Here’s a quick summary of what JPlus offers:

• Full Java compatibility — existing Java libraries and frameworks work without modification.

  • Null safety at the language level (nullable types, safe‑access operator etc.).
  • Type inference, lambda/higher‑order functions, pattern matching.
  • Boilerplate elimination via an apply syntax (for things like data classes, builders, constructors).
  • Gradual adoption model — you can keep using plain Java, and selectively adopt JPlus features.
  • Compilation to plain Java code, so you run on the JVM and benefit from its ecosystem/performance.

My question for the JVM‑community here is:

• Given the current JVM ecosystem (Java, Kotlin, Scala, Groovy, etc.), what are the realistic chances that a language like JPlus could gain mainstream adoption?

• Are there historical patterns for Java superset languages becoming widely adopted?

• What factors might accelerate or hinder adoption for a language that stays close to Java syntax while adding modern features?

I’d love to hear thoughts from people experienced with JVM language evolution, adoption patterns, or designing new JVM languages.