The Hang Seng Index isn't new. The Hang Seng Tech Index is, but I don't think it contains any companies not part of the broader Hang Seng Index. I have no idea how that is supposed to demonstrate the power of the CCP.
The Hong Kong Stock Exchange has been promoting tech listings for years. Recently they have a range of policies such as easier routes to listing for tech companies than for traditional firms. I would not consider a tech index an artifact of Beijing influence, which has its own domestic tech stocks in Shanghai, Shenzhen, etc.
Hang Seng itself is an HK company, has been ever since its inception. HSBC has owned a large part of it for a long time, too.