I don't see this happening in practice. Python has taken over the niche of Perl/PHP/Ruby/Bash almost completely but traditional uses for Java are hardly touched.
VB is dead, the only thing out there right now that seems like it may replace Java is C#.
Scala gets a bad rap from most JVM devs, but Kotlin may be a contender for Java replacement on both mobile and desktop.
Top earners? Likely to stay Java and C/C++ because they're not going anywhere and they're harder to learn than most languages. Maybe Swift for a while too because less people know it (because its Apple specific)