Perhaps the conflict is that you just want to make people who work in ad tech feel bad, and don't care whether or not they enable ICE? That's fine, I suppose, there's industries I feel the same way about. But then we don't have much to talk about and I'm not sure what you hope to gain from being here. To me opposing ICE is very important - I think tobacco companies are pretty bad too, but if ICE sent out a request for cartons of cigarettes I'd shovel praise on them for declining.
Yes—and one of the tools we have for that is shunning.
If enough of us who are appalled and disgusted by the state of things, and the people who willingly lend themselves to creating said state, make our disgust with those people known, it can lead to some of them choosing to act differently, because they care about being thought well of by their fellow techies.