They are inefficient but efficiency only matters in the case that the energy is non solar.

In the case of solar, a kg of hydrogen created, is 33 KWhrs removed from the heat energy of the sun, regardless of efficiency. It doesn't matter if the efficiency is 99 percent or ten percent, that rule has to hold, the only difference is that it takes longer at lower efficiencies than higher, but if you want to create more in a shorter time you just scale up, within the limits of available surface area to cover more area with more panels, and have more electrolysers in inline, and if you are getting revenue from the hydrogen, from what is free energy per kwhr, its win-win, you have the money to replace or replicate hardware, in time.

A 2.4KW electrolyser ("Enapter", for example) running 24/7 will produce about 1kg every 24 hrs.

PS by similar reasoning, the water board, also solar powered as a community similarly has all its revenue needs covered by hydrogen generation, it no longer needs to charge for water, so the water input to the hydrogen is also for free, if all are solar powered.