The Harrier Gr.3 in game with a gross weight of 16,500 LBS as portrayed on the Statshark graph is missing a whole .05 Mach in lift performance.
You can see on the document from the AV-8A manual for an aircraft of 16,500 lbs that it can hit 1G at .2 Mach, 2G at .3, and 7.5G at .66 mach.
In game Statshark graph 1G is at .25 Mach, 2G at .34 Mach, and 7.5G at .69 Mach. The Harrier 1 across the flight envelope is missing lift.