What exactly qualifies as a modern solution that Java(/jvm?) is disqualified?
Syntax, library eco-system, paradigm, type system, cruft? Is "modern solution" some function of blog post count? A social blade type score for how many early-20 somethings are using it?
Or is it going to be something "simplistic" & "clear" which will eventually inherit the cruft all other large languages do?
There's nothing wrong with Perl or PHP either, but plenty of end users have seriously negative associations with the technology and will blame every fault on the technology because it's had a rough history. All of those languages/ecosystems scream "dotcom" to enterprise users and they don't want to hear that they're paying $1.5m for a system that's built in what they consider to be legacy languages.
> that's built in what they consider to be legacy languages
Who's the software company in this situation - you or them or both?
What's the modern solution which they expect you to be on? Go?
What characteristics does it have?
A solution could just as easily be packaged for them in such a way that they just have to run "java -jar someuberjar.jar"