Why people differ sharply over the …

Political leader differed sharply over the question of separate electorates because
(i)  The Nationalist Congress Leaders saw in the Movement the seeds of ‘Divide and Rule’, which weaken the National Movement. This policy of the British would benefit them to maintain their rule over India as long as they wished.
(ii)  The Muslim leaders pretended that their interest could only be protected in a Muslim State, and in a Hindu majority state they would be at the mercy of the Hindus.
(iii) BR Ambedkar, the leader of the depressed classes,  was in favour of separate electorates, because he feared that in a combined electorate, the lower castes would be under the dominance of the upper castes. Gandhiji brought him round to his views by a tactful move by signing a ‘Poona Pact’ with him which provided fixed and reserved seats for the depressed classes.