I've worked on text rendering in the past, and the amount of subtleties in how each language is rendered and the exceptions/code paths that must be implemented to properly support said languages is not insignificant. Mind you, I say this as a native speaker of these languages. I don't want to imagine the amount of effort and work that would be required to support a language I don't speak. Doubly so if I'm not being payed for it.
If you need support for a language you speak, help the developer by implementing and contributing the support yourself.
PS: This isn't aimed at you specifically, but to those who criticize projects for lack of language support without understanding the effort required.