That loudspeaker broadcasting fun "facts" is an interesting way to reeducate captives. IIRC, the consensus among most Western experts is that this type of brainwashing isn't effective.
It's just one component of indoctrination. China also has experiences with prior re-education and work movements. Xi himself was sent to Yunnan (Down to the Countryside Movement) the TLDR is he's a believer. Work camps work, especially on impressionable generations. That's how you create red guards, and why CCP has been trying to ram patriotic education down HK throats. I feel like west likes to reaffirm anecdotes from Chinese cabbies who bitch about the dark times, when in reality those times also forged many believers. People conflate failed economic reforms with failed indoctorination movements. China of that era had much better success re-engineering souls than development - the former merely requires rhetoric which is free, whereas the latter requires capital which is not. Neither words or capital are constraints anymore. Uyghurs also skew young being exempt from family planning policy, so reeducating the youngest generation will shift the entire regions sentiment in 10-20 years assuming the region receives commiserate economic development - hence the vocational training component.