The bickering is from all sides and in case you haven't been following some of the threads on here, I was and still am very critical of the behaviour of the Right of the Party and the PLP for the way they undermined rather than got behind Corbyn from 2015-17, with the only caveat that they did turn out to be right.
From 2017-19 the Left spent more time purging those who opposed them in the Party than they did making themselves a viable option for government. They left Starmer with some serious problems to address, especially the absolute shame of a ECHR report on anti-semitism, but instead of helping him and attacking the Conservatives, they attack Starmer and help the Tories!
The video is produced by Momentum, which was a broad movement of predominantly the young, that was misappropriated and let down by the hard left. I do praise the video and I happily acknowledge they are good at attacking the Tories when they want to. I could have not posted the video at all if I was that factional. The point needs to be made though, the Left too often fight among themselves rather than the Right and that is the biggest reason why the Conservatives are so often in power. So there was praise and important criticism in the same post.