Writing state-of-the art runtimes is probably one of the hardest CS fields. They are way above this “your language sucks” category.

People are human; we get petty and tribal at every level. And ever putting all that aside, if you genuinely believe that one kind of programming or another is the way forward then of course you're going to be more interested in working on technologies that support that.

Even you're maybe right about "the C people" (most of I'm meet were indeed the kind of "there's nothing besides C") this doesn't seem to be relevant here. The JVM is written in C++, not C.

Also there is a large chunk of people (like me) who don't care about Java (the language) but very much about the JVM (and to some degree also about the Java ecosystem). I'm a Scala developer. But I'm also interested lately in Rust (and to some degree C++, as both languages are related), 'cause, you know, max performance and full control, and such.

So at least when it comes to interests there is some pool of people for sure who would like to look into the low-level JVM internals.

The ideal hire would be "language implementation" people. There's a tendency for these to be C/C++ people because these offer conveniences in implementations. But they would also care about other languages and how they work.