Can you explain how muslims have castes?
simple - you have the shia sunni deobandi whabi ahmadi barelvi just to name a few.
you don't call them caste but it is still categorization of people by birth. intermingling amongst these classes and castes are prohibited - you bomb and kill each other!
Atleast the Indian castes, they just didn't touch each other - you guys bomb each other for heavens sake!
Don't tell me you don't know these castes exist in Islam