In The Last Jedi we have the First Order tracking the Resistance through hyperspace, and this is treated as brand new cutting edge technology previously thought to be impossible.
But in the Star Wars Rebels episode "Gathering Forces" (S1 E09), we also have the Empire tracking the crew of the Ghost through hyperspace, via a tracking device that they attached to the ship. The crew of the Ghost does not seem particularly stunned that this tracking technology exists. This is decades before the events of TLJ.
Is this the same technology? If so, why are Finn and Rose so shocked by it in TLJ? is there an in-universe explanation?