JavaScript has a massive and unrivaled ecosystem outside of core data analysis. The main hurdle to adoption is ecosystem and community. A generation of applied mathematicians and data scientists were trained on Python. Python overcame older ecosystems like Matlab and Fortran for its ease of use for other general computing tasks (Matlab is a decent language for large array manipulation but soft tasks like string processing are kludgy compared to Python).

In the same way that Python developers are interested in extending their ecosystem to other spaces, JavaScript developers are interested in growing into the data science space. But that doesn't happen unless there's a clear benefit for switching.

What advantages do a native JS solution have over Python? Performance: There are arguably many more developers and companies focused on pure JS performance than python. Community: A JS solution opens up a much larger pool of talent to build innovative solutions. Cost: Running heavy computations client-side, in the web browser, reduces costs for service providers.

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