Eskéndereyya doesn't only support MSA but other regional derivative languages/dialects like Egyptian and Syrian Arabic. Also, it would be a good idea to refresh your memory and test your knowledge of the language.
I agree with you that the Arabic script is and will always be better for writing Arabic texts but this writing system was developed to fill the gap for beginners and as a stepping stone to the full experience of learning Arabic.
Have you completed the whole guide?
Eskéndereyya doesn't only support MSA but other regional derivative languages/dialects like Egyptian and Syrian Arabic. Also, it would be a good idea to refresh your memory and test your knowledge of the language.
I agree with you that the Arabic script is and will always be better for writing Arabic texts but this writing system was developed to fill the gap for beginners and as a stepping stone to the full experience of learning Arabic.