Are you saying this video is taken out of context? Please do share any available video evidence. I assure you I tried quite hard to try to find more and this all I came up with! This is the thing that most confuses me about these protests. They are, by far, the most widely recorded protests in a developed nation - yet lengthy in context footage of the critical events events is surprisingly difficult to come by. Instead we just get snippets taken out of context that can be framed to show anything you want to show.
For instance this  is Reuters reporting of this video entitled "Dramatic footage captures moment when Hong Kong protester was shot." It strips out absolutely all context and splices the video together in a way that even makes it seem like it's an officer charging a protester who is simply trying to defend himself from an officer drawing a gun. It then includes clips from a police statement which, without the context of what that conflict was about, paired with the selected footage they provided sounds comically absurd.
This is absolutely propaganda, and quite ham handed propaganda at that. But of course there is also extensive propaganda coming from the Chinese side as well. It makes it all extremely difficult to have any clue of what is really happening. If you have any recommendations whatsoever on lengthy uninterrupted film footage on these events, I am absolutely all ears.
 - https://www.reuters.com/article/us-china-anniversary-hongkon...
There's also lots and lots of long-form protest footage available, but you need a Chinese speaker to help you Google your way to it.
I don't speak Chinese or have links handy but it is not hard to find with some help from a native speaker. Dig around LiHKG.