Green hydrogen is developing now, and is very real, and is based on polysilicon solar advancements and PEM electrolyzer advancements, both of which provide ~3 decadal cost-down paths. See these two companies of ours:
Green hydrogen is vapourware.
[1]https://cleantechnica.com/2021/12/22/0-03-of-hydrogen-is-gre...
1 GW per day of new solar is being installed globally. Where do you think the excess mid-day production is going to go? It doesn't have to go anywhere, actually. But it will go somewhere.
If you're championing a tech that based on the one form of it that's basically a rounding-error in the overall prevalence? Yes, that's vapourware.
By your definition, solar was vaporware in 2001 because less than 1 gigawatt per year was built. But it wasn't. It was simply early in its lifecycle. Today, 1 gigawatt of solar is installed in the world every day. Next year China will likely reach 1 TW of annual solar production capacity.
This is perhaps why software people shouldn't throw around the word "vaporware" –- a useful software-industry term –– in hardware-based industries with well developed and well understood generational patterns.