Widths of different uniform distributions along with different centers all still have a quadratic center, so the above argument only needs to be minimally changed.
The added bonus is that if the (1-w^2)^n is replaced by (1-w^a)^n, you can sort of see how to get at the Levy stable distribution (see the characteristic function definition [0]).
The point is that this gives a simple, high-level motivation as to why it's so common. Aside from seeing this flavor of proof in "An Invitation to Modern Number Theory" [1], I haven't really seen it elsewhere (though, to be fair, I'm not a mathematician). I also have never heard the connection of this method to the Levy stable distributions but for someone communicating it to me personally.
I disagree about the audience for Quanta. They tend to be exposed to higher level concepts even if they don't have a lot of in depth experience with them.
[0] https://en.wikipedia.org/wiki/Stable_distribution#Parametriz...
[1] https://www.amazon.com/Invitation-Modern-Number-Theory/dp/06...