There's almost no use for a fixed monospaced Arabic font on Arabic, and even so there's plenty. Most designed Arabic fonts I see today are for the purpose to be used on other designs like on Photoshop, and there's like more freedom and coolness on them than a good font that you will want to publish a book with or use it on your blog.
I think it's the same reason Japan still sticking with their old school looking websites, we are still sticking with our old school fonts.
I think also when there's not much Arabs on big IT company, you never have that Arab guy that can advice that shipping good Arabic fonts on the next OS will be good (except for Linux(s)... Arabic fonts are fine there). I notice also the Arabic version on popular websites normally have a poor choices of words.
I think it's the same reason Japan still sticking with their old school looking websites, we are still sticking with our old school fonts.
I think also when there's not much Arabs on big IT company, you never have that Arab guy that can advice that shipping good Arabic fonts on the next OS will be good (except for Linux(s)... Arabic fonts are fine there). I notice also the Arabic version on popular websites normally have a poor choices of words.