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).

Especially since they put no effort into removing even extensions they know are malicious (and who work very well within the MV3 restrictions): https://palant.info/2025/01/20/malicious-extensions-circumve...