WTH is "salderen" so difficult to implement for Dutch PV owners

The Netherlands use “salderen” for calculation of energy costs.
It would be great to be able to implement this via UI.

How do you expect that to be done? Until your contract year is over, you don’t know how much you used and how much you produced.
So the only moment HA can accurately calculate this, is when you also getting receive your “jaarafrekening” in your inbox