Also in your linked example, you brought up reading and literacy as something that would not improve collective problems, and I couldn't disagree more.
Further, setting up solar + batteries solves a non-modest individual problem, but is not by itself (i.e. reducing carbon footprint; an example mentioned in the parent's link) the solution to climate change. (yes it helps; but incentives leading to people installing solar have a much bigger impact; and the biggest incentive was maybe China building a solar panel industry, but I'm not trying to go down that tangent)
With the solar+battery, I was thinking of solving grid issues and energy prices, which it does do.