If he is correct, Saudi Arabia has decided to abandon support for their jihadists, most of whom came from their prisons; meanwhile Syria, Russia, Turkey, and Iran have decided to wait for the jihadists to deteriorate from the lack of support; and the US-backed Kurdish forces will finally realize that the US can't be relied upon to serve their interests and the US forces will finally leave Syria. Other members of the Arab league will recognize this new political reality and will re-establish ties with Syria. On the other hand, US strategists have extensive experience in creating chaos and will, in my opinion, likely try to stir up more chaos to thwart this scenario. Magnier's geopolitical take on the present situation in Syria seems so sensible, but it also seems too good to be true.
If you are seriously interested in what is going on in the US-backed Kurdish controlled areas of Syria, you might be interested in reading an interview conducted by Sarah Abed, an independent journalist, with Syrian activist and nationalist Nidal Rahawi. See part 1 here, and part 2 here.