Many Arabic-speaking countries already have very high literacy rates. Meanwhile Somali is a related language officially written in the Latin alphabet, but Somal

Many Arabic-speaking countries already have very high literacy rates. Meanwhile Somali is a related language officially written in the Latin alphabet, but Somalia has a literacy rate around 50%: https://ourworldindata.org/grapher/cross-country-literacy-rates?country=EGY~BHR~QAT~SAU~ARE~PSE~OMN~KWT~JOR~TUN~IRQ~MAR~SOM https://ourworldindata.org/grapher/cross-country-literacy-ra... So adopting Arabizi without increasing access to education can be expected to do roughly nothing for literacy, whereas with a good education system, people can learn to read and write in Arabic script just fine.