I think there are low and high Irish and low and high of every group. The Irish and blacks took similar steps. Proving their worth. Starting at the bottom. Both were discriminated against.
Every immigrant is discriminated against.
Some more than others, depending on their status when they get here. Waiters, Pullman porters and red caps working for the railroad were colored. Securities runners at banks were colored. There were a few colored stenographers, but they passed for white. And no one left of their own accord.