> won't catch-up because the language itself has some pain points like type erasure, nullable references (even C# got rid of that), etc. and that won't change ever.

I wouldn't be so sure if I was you. A lot of work is being put into JSpecify [1] lead by Google and with most major players in the Java ecosystem participating. If it is a success we might see it in the language one day and not just with annotations.

[1] https://jspecify.dev/