You clearly are not an xbooks aficionado, you will know that many mutants died from losing their powers some because their power helped their body function others because they couldn't protect themselves from hate crimes. Magma's boyfriend hell into a volcano when decimation happened and burnt to death whilst on a mission. Lately a mutant called lost who has gravity destabilization powers came to krakoa for the crucible because she was in pain without her power. What wanda did had real dire concequence. Mutants died their, they became more susceptible to hate crimes and for most they felt incomplete like a part of them had been ripped away from them it drove some to madness leading to death in some cases.