Well, when they changed alphabet to latin in Turkey, the literacy rate increased with an unbelievable rate. The reason was that latin alphabet is much easier to read than Arabic alphabet. Iran also suffers from high illiteracy rate like most other countries which use arabic script. Also, I saw a research about the reading speed of Iranians, which it showed that it is slower, which not using vowels in writing, ... can be one of main reasons. Also, for non-persian speaking children, it's really difficult to learn farsi with arabic alphabet on an additional hardness level since their vocabulary is already weaker and it's harder for them to speculate what the vowels, and such not shown stuff are. A good comparison can be done by comparing to neighbor countries. while literacy rate in Azerbaijan is 99.8%, Tajikstan 99.7%, and Turkmenistan 98.8%, the literacy rates in their neighbor regions like Ardabil, Golestan, and Khurasan provinces are hardly 80%.
About books, there can be a transitional period in which people learn and use both scripts, then the used older books will be normally written with new alphabet in this period as well, and there will be no cultural gap. Also, finglish is not standardized and more importantly is not taught as the main alphabet to children.
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