Migration from where? What was the population of muslims at the time of invasion? Once having established, they were only interested in amassing wealth, filling up their harems with beautiful women, building monuments, etc. Neither they cared for conversion nor they cared for those who converted to Islam. If they had cared for the common muslims, there was no need for Sachar Commission and things like that. As in any such conflicts, only the poorest of the poor and the indefensible get affected. So the majority of those who were converted were from the lower strata of Indian society and as such the conditions of muslims are also not better than the lower castes from the native religions.
