Indeed, I am also an advocate of having the organization define a specific set of languages.
Even with just one, it isn't really a single one.
To pick on JS as example, not only there is JavaScript to learn, TypeScript might also be part of the stack, then there is the whole browser stack, and eventually node ecosystem as well.
Take the remaining UNIX/Windows related knowledge to get development and deployment into production going, SQL and the related stored procedures syntax for RDMS backends.
Eventually the need to know either C or C++, to contribute to V8 native extensions or WASM.
Now those folks need to learn about Go, Go's standard tooling, Go's ecosystem, IDE or programmer's editor customizations for Go code, and how to approach all the development workflows they are confortable of from the point of view of a Go developer.
Even with just one, it isn't really a single one.
To pick on JS as example, not only there is JavaScript to learn, TypeScript might also be part of the stack, then there is the whole browser stack, and eventually node ecosystem as well.
Take the remaining UNIX/Windows related knowledge to get development and deployment into production going, SQL and the related stored procedures syntax for RDMS backends.
Eventually the need to know either C or C++, to contribute to V8 native extensions or WASM.
Now those folks need to learn about Go, Go's standard tooling, Go's ecosystem, IDE or programmer's editor customizations for Go code, and how to approach all the development workflows they are confortable of from the point of view of a Go developer.