Python predates Julia by 3 decades. In many ways Julia is a response to Python's shortcomings. Julia could've never taken off "instead of" python but it clearly hopes to become the mature and more performant alternative eventually
When Julia came out neither Python nor data science and ML had the popularity they have today. Even 7-8 years ago people we're still having Python vs R debates.
Some small additional details: 23 years not 30. Also, I think Julia was started as much in response to Octave/Matlab’s shortcomings. I don’t know if it is written down, but I was told a big impetus was that Edelman had just sold his star-p company to Microsoft, and star-p was based around octave/matlab.
- https://julialang.org/blog/2012/02/why-we-created-julia/