There's certainly costs involved with solar. Even the act of cleaning the panels is going to increase maintenance costs. More panels to clean, more cost. More space needed for the panels, more cost. It might not be much per panel, but it's still a cost. The wear of the panels is more cost, they only last so long before they degrade, and replacements are not free, so if the panels degrade without doing a lot of "work" (aka the outcome of having them) vs the cost of installing and maintaining them, was it worth it? These are all economic questions that also need to be considered.
Yes, it's not free, but it's the closest thing to "free" power we have. Literally pennies for gigawatt hours of output. If that power isn't consumed, then it wasn't useful to produce. Whether that generated power goes into batteries, homes, or hydrogen production, that's going to be something we have to solve for.
I see a hydrogen reactor + fuel cell "generator" as a secondary storage system to batteries. When production is unusually high, push the power into hydrogen. It's not nearly as efficient, but it can be stored for much longer without losing any. It can be stored far more densely than what can be accomplished by batteries. If the batteries are full and your PV plant is still pouring out unused watts, rather then let that energy go to waste, pushing it into hydrogen storage is a better option. If you don't need it for 6 months, a year, two years? No big deal. When production is low and your batteries are almost out, just fire up the fuel cell and recharge from the excess energy you couldn't put in the batteries. It's inefficient, yes, but bluntly, it's better than letting any of the excess production go to waste.
There's other competing technologies for the same purpose. I see hydrogen as the second stage of storage. It's not as good as the first stage, but it's better than turning to fossil fuels to generate power.
I don't know if that's the right answer to the problem. I don't know if it's even a good idea. All I know is that it is possible. IMO, it's not a bad idea.
I've said it before and I'll say it again: if I'm saying anything at all here, it's that we need to keep researching everything. I don't want anyone to drop research on another technology to dedicate to hydrogen, just as I wouldn't want anyone to drop hydrogen to research something else. We need to keep looking into this stuff.
There's no single solution to our energy needs, as of right now. I don't see one emerging in our lifetimes. The only goal I want to see pursued, if not obtained, is net zero for climate change. Stop the destruction of the environment, especially, but not limited to, our energy needs. Whatever gets us there, whether hydrogen, nuclear, fusion, solid state, flywheel, heat storage, thermoelectric, geothermal, hydroelectric, or whatever... I'm game. I feel like hydrogen still has a lot of discoveries that can be made, and I really don't want to see it abandoned because of a lack of popularity in the consumer space. It's there, it's green, it's got potential, let's keep trying to get it to a place where it can be beneficial, just like with everything else in that market segment.