Most business needs are a cheap version of CRUD+Business Rules.
As a result, the biggest languages (keep in mind that most businesses have large amounts of existing code) are also relatively old (except Go, C# and Swift which are relatively young).
Languages I see with my current clients and have seen with former clients and employers (medium to large organisations):
- Java (Including Scala, Kotlin and Groovy)
- C and C++ (usually both are found at the same company)
- Python
- JavaScript (including TypeScript)
- Web stuff like HTML and CSS (but that's mostly generated now)
- Go
- Swift (and Objective-C, mostly iOS development, some tvOS and macOS)
- C# be it modern or some classic ASP.NET
- A bunch of application-specific languages, Apex/PL-SQL/TSQL/X++
Besides "we already have it" there is the hiring pool problem. If you need to find someone for one of the above languages, the pools are generally big and available enough to find a suitable candidate in a month or two. And as such, if someone leaves you know you'll be able to replace hem.If a platform or application demands a specific language, that's used, but otherwise it's all just availability of people and institutional knowledge.
For your specific languages you might be able to find work at niche sectors like telecom appliance manufacturers, defense or academic institutions.
Edit: and Rust, which like Go, is young (but even younger) yet gaining quite some traction. Also forgot Python for a second there.