Is this fixed cost per filling, or does it include cost of developing the system? I somehow doubt that for all Americans to fill taxes it would cost 6.5b$ (163x40)

I think its like building a bridge analogy, when it costs you to use ferry only 0.01% of price of the bridge. But when its built its essentially free and ferry goes out of business.

Yes that I'd like to hear. It's possible it would be cheaper over time if we assume tax filling is artificially held at a higher price by companies but competition says that shouldn't be true.

But also, the "bridge" is built? There are tons of companies already doing this.