That's a quite unobvious consequence of the software progress. Making software be "a bunch of bricks for creating applications" do come with costs. And the main cost is performance.
As I see on the demo, it evaluates the expression itself. There is a ton of possibilities to misinterpret the domain of operations involved. Moreover, how should we control the details to which it should unwind the undergoing calculations?
That way of work seems a bit too optimistic to me.