Rant: Focus/PIP

TL;DR: Being kicked out just to meet URA targets and not due to performance. I am an L6 with TT (exceeds bar) rating during the last talent calibration and I switched teams 5 months ago. I learned this week that I have been in focus since December and that I can't switch teams. I was taken aback but was not too bothered since I know I can get out of focus. However, all that positivity changed this week. I realized that no matter how much work I put in, my manager keeps nitpicking even the tiniest of things and send an email about it. That's because they got to fill the URA quota. That is there just to kick you out no matter how much of effort you put in. My coworkers apparently aren't nit-picked by my manager because they are not in focus. They are not micromanaged at all while I receive a random email pointing out random flaws in how I prioritize my projects and escalate things. I worked with 3 other managers during my 5 year tenure (of which 2 were at L6 level) at Amazon and I always either met or exceeded expectations. And now my current manager thinks I lack leadership skills. This has been exhausting and I might die of stroke before I get pipped. Being on visa with kids in this tough market makes it even more challenging. Does involving media/labor unions help in any way? I do not want to let this go very easily and stand up for myself. TC: 380, close to 5 years at Amazon