That wasn’t a run away trim event that was an AoA disagree just after rotation. The Fix Boeing implemented to the FCCs disables speed trim system with > 5.5 degrees of AoA split (using mean select value). Leaving the flaps at 1 or 5 is a fantastic idea if you’re going to stay in the pattern. The only thing it stops is the diff feel and speed trim light. So 2 less checklist to run before landing.

That was just an Airspeed un reliable event. Nothing with the trim or any other flight controls.