In the case of the plant pictured in the article, the hydrogen is produced on site from methane. So, at least in that case, from the factory perspective, it is a methane in, ammonia + CO2 out. [1] I don't know how common it is for factories to do both processes at the same site, but that would explain why the article frames it that way.
But beyond that, I think the parent comment is just saying that the price of the hydrogen plays a big role in the availability and price of fertilizer. Even with the current increases in price, it is not profitable to manufacture ammonia using green hydrogen at current market prices.
From the factory perspective, 1 Joule of hydrogen produces more ammonia than 1 Joule of natural gas AND you get to avoid the steam reforming equipment, saving capital & maintenance cost.
And in Europe, at the moment natural gas prices are so high that green hydrogen is now competitive. BUT that’s beside the point.
But beyond that, I think the parent comment is just saying that the price of the hydrogen plays a big role in the availability and price of fertilizer. Even with the current increases in price, it is not profitable to manufacture ammonia using green hydrogen at current market prices.
[1] https://www.cffertilisers.co.uk/about-us/how-our-fertiliser-...