Around 5% of the H2 produced then powers the oxygen production plant, so the system more than pays for itself.
If true it is just the capital for the plant, but that is a big if.
Plants don’t look outlandish. https://www.alibaba.com/showroom/oxygen-plant-cost.html
Being a realist as well as a pessimist I don’t see this as saving consumers a nickel. It will never come to pass unless the public can be dependent on the fuel source and the industry and government can charge and tax enough to keep us in check.