Not sure what you mean by "managed platform". Java being written in C doesn't mean you need to know C to run Java. You hardly deal with any native code at all unless you write your own JNI interface or do some obscure tuning, which is pretty rare.

>The JVM that Java shop is using is likely written in C

Does't this argument cut both ways?

I don’t see how it does at all - the point isn’t C versus Java, it’s native versus managed. Any reasonably proficient team running managed services needs to know how to deal with native dependencies, but the reverse is not true.

not in my view, a person who knows neither java nor c. but i think the counterargument from the people in this thread would make would be something like:

i can write my C programs without ever thinking about java. it is irrelevant to me. however, C is very important for java since the JVM it is running on top of is written in C.

i think, personally, the outcome this type of thinking is that “therefore every java program is in fact just cruft on top of C” which personally as someone who does 80% of their job in SQL i am ill-equipped to object on java’s behalf.

There is more than one JVM,

https://en.wikipedia.org/wiki/List_of_Java_virtual_machines

Most of them don't have a single line of C, rather C++.

Then there are a couple of them like JikesRVM and GraalVM that are meta-circular implementations.

There are Java implementations written in Java and that beloved C compiler nowadays is written in C++.

You’ll note the word “likely” in my comment. And there’s nothing special about C in my argument - I was responding to a comment which used it as an example. The point is simply that one way or another any given team likely knows how to tune, monitor and/or diagnose issues in native bits - in fact even a Java focussed team likely has these skills. But the reverse is clearly not true.