That highlights the flaw of Disney's red card system: it only reflects the wait time that many hours ago.
When you see long lines as WDWNT posted it's because a theater went down between updating the wait times board.
That's not quite how the red cards work.
Red cards go out a minimum of every 10 mins, usually every 5, often every few mins.
Within this the computer creates a table of the active cards. Order scanned and current running time clock and then the last few which made it to the final scan.
The computer can guess the wait time, but typically every 15-30 a coordinator or manager looks at the table and posts the wait time.
When it's really wrong it's human error. Smart coordinator and managers will bump the wait time by a known number the second they lose capacity for whatever reason.
Recap:
FLIK cards measure and show when the card was scanned, how long ago it was scanned, when it is scanned in, and in what order they were scanned.
It'll give them a lot more data points, so it will refresh more frequently if nothing else.
FLIK cards are scanned and sent to the last person in line and scanned right before grouping/boarding.
The RFID in Magic bands would require guests touch two points (and as we've seen with FP that's a choke point) to get the same data.
The long range RFID works for things like names on small world and posters in coaster because they don't need any kind of precision. You pass the area, it "sees" you.
To measure the line it needs to know you're at the end of the line - which could be nowhere near the sensor as many lines often go beyond any physical building - and then at the boarding area. Draw a circle around the loading area in many rides from any fixed point you might install a sensor. Now see how many parts of the queue it would "see" Magic bands in. There are often huge difference in what times from people at the various points it would pick up concurrently and be unable to distinguish.