It's just another symptom of the way this game lazily and imprecisely handles interactions between players.

There's always room for improvement when it comes to things like this. But it'd involve reworking the internal tick rate of the game which would have a significant impact on PvE, whilst also likely requiring significantly more CPU horse power for the zone and instance servers across the board.

PvP would be the biggest winner here, rescue being more responsive would be a comparative side bonus. But if SE considered it to be a worthwhile expense, I suspect they would have done it long ago.