In general JavaScript is eating the world.

Python still dominates in numerical computing and JavaScript hasn't been able to make a single dent. Because nobody wants to write

    a.mul(k).add(b)

rather than

    k * a + b

or

    a.set([i,j], b)

rather than

    a[i,j] = b

JavaScript's lack of operator overloading is keeping Python alive.

Python also has integers that feel part of the language, rather than being segregated from normal numbers in case anybody uses integers by accident.