Despite the hype put forth by the fossil fuel industry seeking to greenwash their product as "hydrogen," electrolysis...
...is a trivial, expensive, and unsustainable route to hydrogen, although I certainly understand that the marketing effort of the fossil fuel industry likes to market it as a "thing."
More than 98% of the hydrogen produced on this planet (for captive use) is produced by the steam reformation of the dangerous fossil fuels, which is, of course, the reason the fossil fuel industry advertises hydrogen claiming, dishonestly, that it's "green."
As is the case with all hydrogen bullshit, electrolysis is a thermodynamic nightmare, even worse than steam reforming since electricity is already thermodynamically degraded, and despite the regular hype about precious metal free electrodes, electrolysis remains restricted by the materials requirements, despite decade upon decade upon decade of "breakthroughs."
The "breakthrough" meme was tiresome all through the late 20th century, and is even worse and more stupid and dishonest in the 21st.