It's not an easy as you think.
-As much as possible, direct salary is most preferred because they can used it right away once they received it unlike in cryptos.
-Even they learned some things needed to work on cryptos like on signature as you mentioned, adults tend to focus in finding jobs around the area because they needed money right away. It will take time to learned signature campaign and with the current status of forum ranking that will be more difficult.
-Online tools. Rather than buying PC or any platforms to accessed the web, a standard family will choose to spend on basic and important needs. Plus accessing internet also has a cost which I doubt poor families will prioritized it first.