Literacy rates in India look to be ~80% and climbing about 1% per year. Obviously it'll reach an asymptote, but it's looking like India already surpasses the US in this regard. Of course, given the large population, more Indians are illiterate than there are people in almost every nation. Nonetheless, wouldn't this solution be quite niche?
Source: https://www.macrotrends.net/countries/IND/india/literacy-rat...