I had asked this question before to a tech pilot, they *believe*, that it is a cue to help show the flightcrew that the control column should have light forward force applied for nosewheel steering affectivness as indicated below by the b737 FCTM, then transition to a nuetral stick force around 80 kts (but this does not co-incide with the FD vertical re-positioning back up at 60kts??
"Light forward pressure is held on the control column. Keep the airplane on
centerline with rudder pedal steering and rudder. The rudder becomes effective
between 40 and 60 knots. Maximum nose wheel steering effectiveness is available
when above taxi speeds by using rudder pedal steering."
"Above 80 knots, relax the forward control column pressure to the neutral position."