Sorry trim is not only used for take off. Trim main use is to keep airspeed. On any phase of the flight you choose speed and trim it will fly… Becos it changes angle of the plane. You don’t have to keep hold of yoke all the way. On take off it changes angle to create lifts… Same it sets right angle trim so aircrafts will achieve optimum air flow over wings on lift.
It will come handy on level flight, set power, trim, it release pressure on yoke.
On approach you choose descent rate, set power, trim, it will fly nicely without you playing with thrust and pitch.