You are being way too charitable. The five demands materialized out of one demand ("don't rush the bill") after Carrie Lam made a concession to suspend the bill. Middle-of-the-road concessions are not what the protestors are looking for now, if they ever were. Indeed they have indicated a strategy to use this moment to extract the maximal concession. That's a fairly extremist position that is probably unwise, and leads to all sorts of problems like having to buttress their own weak power position with borrowed foreign leverage.

The PRC leadership is not stupid, either. They see the suspension of the bill as test of whether this whole thing was about the bill or something else. As suspected, it was about something else. Given that, no concession the PRC is willing to make will be enough. This is bigger than HK now and frankly out of HK'ers hands as to how it evolves next.