honestly kill monger as a character was sympathetic but what he was doing made no sense and is completely different from what the x-men are doing. Killmonger decided because he was rejected he would team up with his oppressors to steal a throne rather than try to contact wakanda and make things better for others back home.
mutants did not team up with their would be oppressors and instead decided to carve out a section of earth for themselves to find peace and then offered help to those who oppressed them rather than set out to actively destroy and take from them.
But both being rejected are similar. Except Wakanda tried to embrace killmonger and they also stood back and let him challenge tchalla where as humans have not even afforded that to mutants. The respect of their own laws.