Matrix operations are already built-ins in Julia. And it's such a pleasant to work with compared to the syntax of Numpy. People just don't want to get away from the familiar thing (i.e. Python).

And I don't think making a web framework would be a focus of Julia since it was built with science and computing mindset.

This might be cliché but use right tools for the job. I still use Ruby for web development and Julia for the science and machine learning stuffs (gradually moved from Python ecosystem).