“. isn’t the market moving against traders because they are exiting opposite positions? ”
To make a long story short, no.
First of all, the market moves against DM traders who opened positions / their positions already in the market.
Once a group of DM traders got stop-hunted (= kicked out), you can see the price “breathing” back towards the range. That is like what Djamal calls a “post-stop hunt move”.
Also, the SM algos do not need to “mirror” any DM positions “1:1”, because they have full price control. Yes, the SM will “cash in” on a regular basis, but their own overall net exposure can be different, sometimes even opposite from their most recent cash in.