I disagree that this is an example of the "cobra effect". That term properly refers to situations where efforts to improve a problem have misaligned incentives

I disagree that this is an example of the "cobra effect". That term properly refers to situations where efforts to improve a problem have misaligned incentives that wind up exacerbating the same problem. Ideally, we'd have fulfilling, well-paid jobs for everyone. If we can't have that, at least robots don't suffer when you make them do mindless, repetitive tasks at high speed for no money. The status quo is humans suffering in miserable jobs. A unionization push that results in better-paid, more humane jobs in the short term, and robots taking over the awful jobs in the long run seems like a net gain for humanity to me. One way or another, we're going to have to figure out what humans do in an automated world, because the robots are coming for everyone's job, not just warehouse workers. (Unless climate change stress collapses society before then, which might happen)