If the internship pay is good enough, they will be very willing to learn Mandarin.
This is why I want to open it up, as I said in my original message. Get the young Hong Kongers out of Hong Kong. Let them go where they can learn the truth.
The pro-Beijing media can last as long as necessary, if they are subsidized by Beijing. Besides, if they consistently tell the truth, the people will notice. The pro-mainland media could even become profitable!
I understand what you're trying to say here but I would argue that it is a lost cause for these youngsters. Many of these rioters do speak some Mandarin(Mandarin is taught in Hong Kong schools) as they would often go to Shenzhen for works, for shopping, and for entertainment. It is not like they have zero exposure to mainland. Instead the central government needs to focus on the education system in HK especially for elementary and high schools as those kids still can be changed.
Look up selective exposure theory and confirmation bias, "individuals' tendency to favor information which reinforces their pre-existing views while avoiding contradictory information and the tendency to search for, interpret, favor, and recall information in a way that affirms one's prior beliefs or hypotheses." It is too late for these youngsters and only some of them would wake up someday and realize how wrongs they were.
The truth doesn't matter when people don't seek them. There are many pro-Beijing media and they don't have problem for surviving but what good for a media when it is not widely distributed. It is never about the truth but more about reaching, connecting with and resonated with the people especially the youngsters. In this regard, pro-Beijing failed badly as most youngsters don't read them. The sad thing is that FB, twitter, and youtube which are popular in HK are actually helping the rioters and undermining the pro-Beijing supporters.