The other reason is that the capsule can splashdown far away from the ship. In this case it was close (3km or so). It can possibly fall much farther away. In which case boats would be much slower. Add in the possibility of rough seas & bad weather the helos make sense. And just to keep things simple I think they just use them no matter what. Prevent errors. Also gives a chance to rehearse and debug the full recovery process in case it’s actually really needed the next time.