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Javascript doesn't "need" dependency injection because modules are objects, and you can mock those directly by replacing what they reference to. Very similar story in python. You could say people do DI in these dynamic languages without calling it DI.

Now Java and C# are different because they are compiled. You need a DI tool to do dynamic dispatch if you want to mock.

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It's all aspects of the same thing.

You can't inject a nuclear reactor into a burrito in any language untyped or not because it will lead to an error.

The only difference is python/js the error will happen at runtime while in C$/java the error happens at compile time.

The main difference is the type. In typed languages you need describe am interface or a class of types if you want to do mocking or dynamic dispatch while in dynamic languages you don't need to explicitly define this as a type, the definition exists in how you use the object that is passed in.

Either way DI, however universal, in any language is bad practice.

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