Pick the Fortune 500 list, take out the SV darlings, the majority of their backend stacks will be a mix of Java and .NET deployments.
Easy to find out just by looking at their open job positions.
Easy to find out just by looking at their open job positions.
Microsoft is an exception because they built C# which is basically a more modern but less popular variant of Java. There was even a project for a long time that let you use Java code in C# projects by converting the bytecode, they're that similar.
The notable exception is Facebook. They were stuck in PHP hell for so long that they redesigned the language to make it work.