Why there is still no Tibetan language on iOS?

Many Tibetans buy iPhones because they dispaly Tibetan. However, now (in 2016), since Google made Android Marshamllow display Tibetan, the Chinese leading tech companies have put Tibetan language pack on their OS based on Android M(6.0). For example, Huawei's EMUI 4.0 and Xiaomi's MIUI 8 have full OS in Tibetan language. Thus, I think Apple really should make Tibetan option availible on iOS and also should considering change the font.