Regarding the Cultural revolution it was largely a failure but there were good things and reading/nuance goes beyond just “Mao's motivations” or students bullying teachers . Even if the CR aimed at a path opposing the path China actualy took (which as a critical supporter of modern china i must say that it probably ended up being the correct one) .

The focus on the modern western liberal narrative and even left's understanding is on Mao and the violence of the “red guards” but that is to ignore at the beginning CR , while things were far from the chaos and mistakes that errupted later on , bureaucrats and leading party members like Liu Shaoqi and even Deng wanted to turn the CR into a wider Anti-leftist Campaign and sent their people to the provinces to crush "ultra left" dissidents in the name of the CR. The first actualy hard stance and leading involvement of Mao in the whole deal was to support the students opposing them, which was where “Bombard The Headquarters” came from, and that (at the very least “both-sides”) conflict was whats turned the CR as a radical mass and mess of a movement (1966-1968) began. The political violence of the Cultural Revolution was oversimplified in the mainstream histories and popular media, even ones coming out of China like the one you mention.

More specificaly, the first phase of the Cultural Revolution, also the most brutal in terms of number of deaths divided by number of days, was under the direct control of mainly Liu Shaoqi and Deng Xiaoping, who used it to “purge down”, i.e. killing all kinds of dissidents from “questionable” families. Mao was justifiedd in supporting the rebels (or left Red Guards) to “bombard the headquarters” and “purge up” instead, i.e. targeting the capitalist roaders in the ruling class in theory. In practice there were massive excesses and chaos and the complete decentralization of the movement meant a lot of groups acted way different;y, even yes purging and killing professors or destroying historical artifacts. But as a whole arguably the most oppressed group of people of the entire period were the rebels, the sincere Maoists, who lost power after 1968 and only rose to prominence again intermittently, mainly with the support of Mao. They suffered deaths and persecution first during the “Liu-Deng Cultural Revolution”, then during the “order-restoring purges” of 1968-1969, and again under Hua Guofeng and Deng Xiaoping during the “Gang of Four trial”. You can and should argue about the probability that China is now better for it but historicaly that is the truth

Even Maurice Meisner, generally critical of Mao, wondered why in popular discourse it’s all about “young Red Guards beating up disgraced officials and intellectuals”, while in fact most deaths of that period were young Red Guards being slaughtered by local conservative officials after the decline of mass movement at the end of 1968 and at the start of its rise. So the BAD that happened during it (and there was a lot) were far from just “Ultra Maoist theory and practice gone wrong” or deserved to be blamed on Mao and the red guards nearly as much as it is even in leftist spaces. So im being 50-50 on it because of the totally wrapped idea and history of why it was bad and who did what. It wasnt allowed to succeed or fail in its own merrits and in practice was largely a failure because it was massively supressed and made magnitudes worse by the opposing faction even if you can certainly argue that if it went as planned that China would be in a worse position today

In general the idea of a second revolution within the state is something every leftist should consider in terms of what comes next, especialy in states and countries that have internalized capitalist and bourgois hegemony, tendencies and mindset for so long…Even in China’s case the example of a tendency toawrds petit bourgeois, and that the restoration of capitalism leading to the CR began in the countryside with the household responsibility system not introduced o, which went smoothly because it’s popular, popular because it satisfied the peasant’ ingrained by centuries desire to be private, autonomous producer on his own land and not as a collective and workers community. Mao himself was aware of this, and one of the most frequently used quote in the CR was Lenin on “small producers everyday reproducing capitalist relations”

To counterbalance the violence from both sides which i have posted about thus far, some general positives that happened during it were the promotion of egalitarian spirit against the revisionist’s USSR model of clearly defined and explicitly unequal income and power distribution between different levels of bureaucrats and employees, a surge of Industrial democracy and people’s rule in factories ,attempts at overcoming division of labor as an obstacle to socialism, theory of permanent revolution under and within the dictatorship of proletariat ,export of revolution: many insurgencies still going strong (Naxalites and NPA)

But beyond the chaos after it balooned up into large scale confrontation of big party and leftist factions it mainly failed because Objective material conditions: Chinese overwhelmingly peasants (having to go through and form local capitalist units of production with Dengs “chinese dream” policies which in retrospect you can argue succeeded ), older ages “tired” of constant revolutionary vigor, big changes and lack of stability and normality during Mao’s rule ,some his fault some dont