This feels more like a gradual tightening of extension APIs under Manifest V3 than a sudden “kill switch.” uBlock isn’t going away, but its capabilities are definitely being reshaped...
It's all an excuse to try to neuter adblockers. The push for killing MV2 was suspiciously accelerated at the same time that youtube started implementing much more invasive anti-adblock techniques that really needed a full content blocker support (at least until people found new clever workarounds).