Portfolio vs Highlevel board - What's the difference?

I’ve just started playing around with the new Portfolio/Project system. Although useful, as far as I can see, it looks like a sophisticated standard high level/low level board setup with resource tracking; but nothing that can’t already be done. We already have that kind of board setup. Is there something I’m missing? Is there a difference to the Portfolio system that you can’t replicate in a standard setup?

Or is it just that this is the most common complex setup that people use so they’ve made a nice template for it?