I think the ones taking these lectures are execs and other variety of leeches at Chinese banks or other other Chinese institutions or organisations. The original source at Bloomberg says:

At a Beijing-based state-owned energy company some employees said they were increasingly being dragged into impromptu training during working hours. Such sessions, often centered around Xi’s latest remarks, were held at an isolated facility with mobile phones confiscated sometimes, making it hard for coworkers to reach out to them in case of a work-related emergency, according to these employees, who asked not to be identified as the matter is private.

Some bank executives and business heads have to take around a third of working time to study Xi Thought, joining activities and courses, or reading four books from Xi every month, according to people familiar with the matter. Attendance is mandatory this year and they also need to submit papers on what they’ve learned.

At the same time, bankers have seen steep cuts in salaries and the rollback of many perks, such as business travel, all to comport with a key tenet of Xi Thought: “common prosperity.”

https://archive.ph/tbvpL