not all topspin groundstrokes are high clearance loopy shots. For a lot of pros they use heavy topspin and low/moderate net clearance to have the ball kick forward, or create an angle across court. or to ensure that the ball doesn't bounce out behind the baseline when hit with pace.
topspin =/= high clearance in all cases.
Disclaimer: I'm NOT a coach...
Real tennis: https://www.youtube.com/watch?v=yDqnkLJ9BtM