I don’t think you are right. Or maybe Israeli Arabs and Palestinians serve the military in a different way.
Bedouins and Druze as far as I know are the only ones that serve in the military proper.
Israeli Arabs and Palis are few and far betwen in IDF, but I’ve read an article about an East Jerusalem pali serving, and how his family and the IDF had to keep his enlistment secret for fear of reprisals, and I’ve met an Arab from Um ElFacham who was serving on the police force in Hevron.