So basically only India disengaged and not China?
Actually a bit correction at some places, chinese did move back a bit, but the problem is both moved back the same amount.
So, if X (indian control point) and Y (chinese control point), we 5 kms apart (buffer zone), and China moved to X for standoff. Now, even if both China and India decide to move back 2.5 km, India still loses 2.5 kms.
If differs from point to point. Apparently they came in the most in depsang plains.
Also, China used the stand off to build up permanent shelters and bases few kms behind line of control on their side (india is also doing the same apparently now). That means LAC has now become defacto LOC, that is highly militarized with permanent bases like our LOC with Pakis.