It's also a weird thing to bring up (Numba being great because it can jit-compile python to any arch, including GPUs) when the author discounted Julia... which has exactly the same property.
The difference is uptake. Julia's good and it's out there, but relative to the users of Python... How many people care how portable the Julia code they aren't writing is? The existence of a tool to jit-compile Python is more useful to a lot more engineers than the existence of another language that is nicely jit-compileable.
Right, except the author also mentions two obscure languages with very little uptake at all, so it can't simply be a popularity thing - they're not useful at all, by that limited metric.