Disruption of the staging areas would have hindered the flow of building materials to develop port and airfield facilities. Even IOTL American forces (despite occupying the Philippine islands for over 40 years prior) had staggeringly little knowledge of the terrain of Leyte, and the ground battle there consumed far more for far less return than was anticipated. Both contemporaries and subsequent historians have since lambasted the US performance:
But again, the disruption would have only been a few days and the American armies ashore could easily pause and assume the defensive to wait out the period of interruption. Once Kurita's force is dead, the US's mass of shipping would easily be able to replace the losses and things could resume as before. The development of events would be delayed, but that's not the same as them being changed.